From fffcc90da91b66ee607066d410b57f34024bd1de Mon Sep 17 00:00:00 2001
From: Jovina Dsouza
Date: Mon, 7 Jul 2014 16:34:28 +0530
Subject: adding book

---
 Electronics_Devices_And_Circuits/Chapter2.ipynb    |  567 +++++++
 Electronics_Devices_And_Circuits/Chapter6.ipynb    |  545 +++++++
 Electronics_Devices_And_Circuits/chapter1.ipynb    | 1579 ++++++++++++++++++++
 Electronics_Devices_And_Circuits/chapter10.ipynb   |  458 ++++++
 Electronics_Devices_And_Circuits/chapter11.ipynb   |  170 +++
 Electronics_Devices_And_Circuits/chapter3.ipynb    | 1540 +++++++++++++++++++
 Electronics_Devices_And_Circuits/chapter4.ipynb    | 1211 +++++++++++++++
 Electronics_Devices_And_Circuits/chapter5.ipynb    |  653 ++++++++
 Electronics_Devices_And_Circuits/chapter7.ipynb    |  645 ++++++++
 Electronics_Devices_And_Circuits/chapter8.ipynb    |  435 ++++++
 Electronics_Devices_And_Circuits/chapter9.ipynb    |  181 +++
 .../screenshots/snap_4.1.png                       |  Bin 0 -> 51900 bytes
 .../screenshots/snap_5.1.png                       |  Bin 0 -> 53409 bytes
 .../screenshots/snap_7.1.png                       |  Bin 0 -> 50825 bytes
 14 files changed, 7984 insertions(+)
 create mode 100755 Electronics_Devices_And_Circuits/Chapter2.ipynb
 create mode 100755 Electronics_Devices_And_Circuits/Chapter6.ipynb
 create mode 100755 Electronics_Devices_And_Circuits/chapter1.ipynb
 create mode 100755 Electronics_Devices_And_Circuits/chapter10.ipynb
 create mode 100755 Electronics_Devices_And_Circuits/chapter11.ipynb
 create mode 100755 Electronics_Devices_And_Circuits/chapter3.ipynb
 create mode 100755 Electronics_Devices_And_Circuits/chapter4.ipynb
 create mode 100755 Electronics_Devices_And_Circuits/chapter5.ipynb
 create mode 100755 Electronics_Devices_And_Circuits/chapter7.ipynb
 create mode 100755 Electronics_Devices_And_Circuits/chapter8.ipynb
 create mode 100755 Electronics_Devices_And_Circuits/chapter9.ipynb
 create mode 100755 Electronics_Devices_And_Circuits/screenshots/snap_4.1.png
 create mode 100755 Electronics_Devices_And_Circuits/screenshots/snap_5.1.png
 create mode 100755 Electronics_Devices_And_Circuits/screenshots/snap_7.1.png

(limited to 'Electronics_Devices_And_Circuits')

diff --git a/Electronics_Devices_And_Circuits/Chapter2.ipynb b/Electronics_Devices_And_Circuits/Chapter2.ipynb
new file mode 100755
index 00000000..4eb7e136
--- /dev/null
+++ b/Electronics_Devices_And_Circuits/Chapter2.ipynb
@@ -0,0 +1,567 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:7b8ef11e11019a3b1cc284475151e0d8bb5d6632f9c468e0f90289ce47134c38"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "                                   Chapter 2: TRANSISTORS AND OTHER DEVICES"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 2.1,Page number 89"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Rb=200                  #base resistance(ohm)\n",
+      "Vbe=0.7                 #base emitter voltage drop(V) in active region          \n",
+      "Vbb=5                   #base voltage of bipolar transistor(V) \n",
+      "beeta=100               #current gain\n",
+      "Rc=3                    #collector resistance(k ohms)\n",
+      "Vcc=10                  #voltage given to the collector(V)\n",
+      "\n",
+      "#Calculations\n",
+      "Ib=(Vbb-Vbe)/Rb           #base current(mA)  \n",
+      "Ic=beeta*Ib               #collector current(mA) \n",
+      "Vcb=-Vbe-(Rc*Ic)+Vcc      #collector base voltage drop(V)\n",
+      "\n",
+      "#Results\n",
+      "print\"base current\",Ib,\"mA\" \n",
+      "print\"collector current\",Ic,\"mA\"\n",
+      "print\"reverse bias collector junction is\",Vcb,\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "base current 0.0215 mA\n",
+        "collector current 2.15 mA\n",
+        "reverse bias collector junction is 2.85 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 2.2,Page number 90"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vbb=5               #base voltage of bipolar transistor(V)\n",
+      "Vbe=0.7             #base emitter voltage drop(V) in active region  \n",
+      "Rb=150              #base resistance(ohm)\n",
+      "beeta=125           #curret gain     \n",
+      "Rc=3                #collector resistance(k ohms)  \n",
+      "Vcc=10              #supply voltage(V)\n",
+      "Vce=0.2             #collector to emitter voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Ib=(Vbb-Vbe)/Rb       #base current(mA)\n",
+      "Ic=beeta*Ib           #collector current(mA)\n",
+      "Vcb=-Vbe-(Rc*Ic)+Vcc  #collector base voltage drop(V)\n",
+      "\n",
+      "#Part b -for npn transistor\n",
+      "Vbe=0.8             #base emitter voltage drop(V) in saturation\n",
+      "Ic=(Vcc-Vce)/Rc     #collector current(mA)\n",
+      "Ib=(Vbb-Vbe)/Rb     #base current(mA)\n",
+      "Ibmin=Ic/beeta      #minimum base current(mA) to go into saturation(mA)\n",
+      "\n",
+      "#Results\n",
+      "print\"In active region, base current is\",round(Ib/1E-3),\"*10**-3 mA and collector current is\",round(Ic,2),\"mA\" \n",
+      "print\"base current and collector current in npn are\",round((Ib/1E-3),2),\"*10**-3 mA\",\"and\",round(Ic,2),\"mA resp.\"\n",
+      "print\"base current minimum is\",round(Ibmin,3),\"mA\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "In active region, base current is 28.0 *10**-3 mA and collector current is 3.27 mA\n",
+        "base current and collector current in npn are 28.0 *10**-3 mA and 3.27 mA resp.\n",
+        "base current minimum is 0.026 mA\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 2.3,Page number 91"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vbb=5                 #base voltage of bipolar transistor(V)\n",
+      "Vbe=0.7               #base emitter voltage drop(V) in active region  \n",
+      "Rb=50                 #base resistance(ohm)\n",
+      "beeta=50              #current gain\n",
+      "Re=1.8                #emitter resistance(k ohms)    \n",
+      "Vcc=10                #supply voltage(V)\n",
+      "Vce=0.2               #collector to emitter voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "Ib=(Vbb-Vbe)/(Rb+Re*(beeta+1))      #base current(mA)\n",
+      "Ic=beeta*Ib                         #collector current(mA)\n",
+      "Ie=Ib+Ic                            #emitter current(mA)\n",
+      "\n",
+      "#Results\n",
+      "print\"values are Ib:\",round(Ib,2),\"mA,Ic:\",round(Ic,2),\"mA and Ie:\",round(Ie,2),\"mA\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "values are Ib: 0.03 mA,Ic: 1.52 mA and Ie: 1.55 mA\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 2.4,Page number 91"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vbe=0.7                      #base to emitter voltage(V)\n",
+      "Rb=250                       #base resistance(k ohms)\n",
+      "Vcc=10                       #supply voltage(V)\n",
+      "Rl=0.5                       #load resistance(k ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "Ic=Vcc/Rl                    #collector current(mA)\n",
+      "IbQ=(Vcc-Vbe)/Rb             #Ib at operating point(uA)\n",
+      "IcQ=8                        #Ic at operating point(mA)\n",
+      "VceQ=6                       #Vce at operating point(V)\n",
+      "\n",
+      "#Results\n",
+      "print\"values are IbQ:\",IbQ,\"uA,IcQ:\",IcQ,\"mA and Vcc:\",Vcc,\"V\"\n",
+      "print\"collector current Ic is\",Ic,\"mA and output voltage,vL=6-2 sinwt V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "values are IbQ: 0.0372 uA,IcQ: 8 mA and Vcc: 10 V\n",
+        "collector current Ic is 20.0 mA and output voltage,vL=6-2 sinwt V\n"
+       ]
+      }
+     ],
+     "prompt_number": 6
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 2.5,Page number 104"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vgs=12                   #gate to source voltage(V)\n",
+      "Vt=4                     #threshold voltage(V)\n",
+      "Id=12.8                  #drain current(mA)\n",
+      "K=0.0002                 #device parameter \n",
+      "Vdd=24                   #drain voltage(V)\n",
+      "Vds=Vgs=8                #drain to source voltage(V)      \n",
+      "\n",
+      "#Calculations\n",
+      "Id=K*((Vds-Vt)**2)       #drain current at Vds=8V\n",
+      "Rd=(Vdd-Vds)/Id          #drain resistance(k ohms)\n",
+      "\n",
+      "#Result\n",
+      "print\"diode resistance is\",Rd,\"ohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "diode resistance is 5000.0 ohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 2.7,Page number 106"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vds=7.5                #drain to source voltage(V)\n",
+      "Id=5                   #drain current(mA)      \n",
+      "\n",
+      "#Calculations\n",
+      "Vgs=-1.5               #gate to source voltage(V)\n",
+      "Vgg=-Vgs               #gate voltage=gate to source voltage(V) \n",
+      "\n",
+      "#Result\n",
+      "print\"gate voltage is\",Vgg,\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "gate voltage is 1.5 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 5
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 2.8,Page number 107"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vds=7.5                  #drain to source voltage(V)\n",
+      "Idss=8.                  #drain current for Vgs(V)\n",
+      "Vgs=2.                   #gate to source voltage(V)\n",
+      "Vp=4.                    #peak voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "Id=Idss*((Vp-Vgs)/Vp)**2  #drain current(mA)\n",
+      "\n",
+      "#Result\n",
+      "print\"diode current is\",Id,\"mA\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "diode current is 2.0 mA\n"
+       ]
+      }
+     ],
+     "prompt_number": 13
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 2.10,Page number 115"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "beeta=160               #current gain\n",
+      "Vee=10                  #emitter voltage(V)\n",
+      "Rb=400                  #base resistance(k ohms)\n",
+      "Veb=0.8                 #emitter to base voltage(V)\n",
+      "Re=2.5                  #emitter resistance(k ohms)\n",
+      "Rc=1.5                  #collector resistance(k ohms)   \n",
+      "\n",
+      "#Calculations\n",
+      "#Part a \n",
+      "Ib=(Vee-Veb)/((Re*(1+beeta))+Rb)    #base current(uA)\n",
+      "Ic=beeta*Ib                         #collector current(mA)\n",
+      "Ie=(beeta+1)*Ib                     #emitter current(mA) \n",
+      "Vce=Vee-(Re*Ie)-(Rc*Ic)             #emitter to collector voltage(V)   \n",
+      "Vce=-Vce                            #collector to emitter voltage(V)\n",
+      "\n",
+      "#Part b\n",
+      "beeta=80                            #current gain \n",
+      "Ib1=(Vee-Veb)/((Re*(1+beeta))+Rb)   #base current(uA)\n",
+      "Ic1=beeta*Ib1                       #collector current(mA)\n",
+      "Ie1=(beeta+1)*Ib1                   #emitter current(mA)   \n",
+      "Vce1=-(Vee-(Ie1*Re)-(Rc*Ic1))       #collector to emitter voltage(V)   \n",
+      "                      \n",
+      "#Result\n",
+      "print\"collector current and Vce for beeta=160 are\",round(Ic,2),\"mA\",\"and\",round(Vce,2),\"V\" \n",
+      "print\"Ic and Vce for beeta=80 are\",round(Ic,2),\"mA\",\"and\",round(Vce1,2),\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "collector current and Vce for beeta=160 are 1.83 mA and -2.63 V\n",
+        "Ic and Vce for beeta=80 are 1.83 mA and -5.08 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 7
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 2.13,Page number 120"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "from sympy import*\n",
+      "import math \n",
+      "\n",
+      "#Variable declaration\n",
+      "K=2                      #device parameter\n",
+      "Rd=Rs=2.5*10**3          #drain resistance(k ohms)\n",
+      "R1=100*10**3             #resistance(ohms)\n",
+      "R2=200*10**3             #resistance(ohms)\n",
+      "Vdd=12                   #drain voltage(V)\n",
+      "Vt=4                     #threshold voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "Vgg=(R2*Vdd)/(R1+R2)\n",
+      "Id=symbols('Id')                         #gate voltage(V)\n",
+      "expr=solve(Id**2-3.28*Id+2.56,Id)\n",
+      "print expr\n",
+      "Id=1.28\n",
+      "Vds=Vdd-5*Id\n",
+      "\n",
+      "#Result\n",
+      "print\"Id is\",Id,\"mA and Vds is\",Vds,\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "[1.28000000000000, 2.00000000000000]\n",
+        "Id is 1.28 mA and Vds is 5.6 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 10
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 2.14,Page number 121"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "k=2.                       #device parameter\n",
+      "Vt=-1.                     #threshold voltage(V)\n",
+      "Vdd=-12.                   #drain voltage(V)\n",
+      "R1=300.                    #resistance(kohms)\n",
+      "R2=100.                    #resistance(kohms)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Vgs=-2                  #gate to source voltage(V)\n",
+      "Vgg=(R2*Vdd)/(R1+R2)    #gate voltage(V)\n",
+      "Id=k*((Vgs-Vt)**2)      #drain current(mA)\n",
+      "Rs=(Vgs-Vgg)/Id         #source resistance(k ohms) as Id=Is,Kvl in GS loop\n",
+      "Is=Id\n",
+      "\n",
+      "#Part b\n",
+      "Vds=-4                    #drain to source voltage(V)\n",
+      "Rd=(-Vdd+Vds-(Is*Rs))/Id  #applying kvl in DS loop\n",
+      "\n",
+      "#Part c \n",
+      "Vt=-1.5                      #threshold voltage(V)             \n",
+      "Vgg=-1.5                     #gate voltage using Id formula    \n",
+      "R2new=(Vgg*R1)/(Vdd-Vgg)     #new resistance(k ohms)\n",
+      "\n",
+      "#Results\n",
+      "print\"a)source resistance is\",Rs,\"kohm\" \n",
+      "print\"b)drain resistance is\",Rd,\"kohm\"\n",
+      "print\"c)R2new is\",round(R2new,2),\"kohm\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)source resistance is 0.5 kohm\n",
+        "b)drain resistance is 3.5 kohm\n",
+        "c)R2new is 42.86 kohm\n"
+       ]
+      }
+     ],
+     "prompt_number": 6
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 2.15,Page number 122"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Vp=-4                    #peak voltage(V)\n",
+      "Idss=10                  #drain current for Vgs(V)\n",
+      "Vdd=18                   #drain voltage(V)   \n",
+      "Rs=2               #source resistance(ohms) \n",
+      "Rd=2               #drain resistance(ohms)\n",
+      "R1=450*10**3             #resistance(ohms)\n",
+      "R2=90*10**3              #resistance(ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "Vgg=(R2*Vdd)/(R1+R2)\n",
+      "from sympy import*\n",
+      "Id=symbols('Id')\n",
+      "expr=solve(20*Id**2-148*Id+245,Id)\n",
+      "print expr\n",
+      "Id1=2.5\n",
+      "Vds=Vdd-((Rs+Rd)*Id1)\n",
+      "\n",
+      "#Result\n",
+      "print\"Id is\",Id1,\"mA and Vds is\",Vds,\"V\"\n"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "[5/2, 49/10]\n",
+        "Id is 2.5 mA and Vds is 8.0 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 20
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 2.16,Page number 123"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Vp=4                    #peak voltage(V)\n",
+      "Idss=12.                #drain current for Vgs(V) \n",
+      "Vdd=12                  #drain voltage(V)\n",
+      "Id=4.                   #drain current(mA)\n",
+      "Vds=6                   #drain to source voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "Rs=(Vp/4)*(1-(math.sqrt(Id/Idss)))      #by Id=Idss(1-(Vgs/Vp))^2 and putting Vgs=4Rs in it and solving\n",
+      "Rd=((Vdd+Vds)/Id)-Rs                    #solving equation -Vdd-Vds+(Id*(Rd+Rs))=0      \n",
+      "                                             \n",
+      "#Result\n",
+      "print\"source resistance is\",round(Rs,2),\"kohm\" \n",
+      "print\"drain resistance\",round(Rd,2),\"kohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "source resistance is 0.42 kohm\n",
+        "drain resistance 4.08 kohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Electronics_Devices_And_Circuits/Chapter6.ipynb b/Electronics_Devices_And_Circuits/Chapter6.ipynb
new file mode 100755
index 00000000..721c027d
--- /dev/null
+++ b/Electronics_Devices_And_Circuits/Chapter6.ipynb
@@ -0,0 +1,545 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:b6947316bc65682adaa8d93a4eda990ab9271382dd0514c03ae855d300a77db0"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "Chapter 6: Feedback Amplifiers And Oscillators"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 6.1,Page number 331"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vo=12.            #output voltage(V)\n",
+      "f=1.5*10**3       #frequency(Hz)\n",
+      "h=0.25            #second harmonic content(%) \n",
+      "ho=2.5            #reduced harmonic content of output(%)\n",
+      "A=100             #power amplifier gain\n",
+      "\n",
+      "#Calculations\n",
+      "Vd=Vo*h              #second harmonic content in output(V)\n",
+      "Vd1=Vo*ho            #reduced value of second harmonic content(V)\n",
+      "beta=((Vd1/Vd)-1)/A  #feedback gain from formula Vd1=Vd/(1+beta*A) \n",
+      "Vs=Vo*(1+beta*A)/A   #signal voltage(V) from formula (A/(1+Beta*A))*Vs \n",
+      "V=Vo/A               #signal input needed without feedback        \n",
+      "s=Vs/V               #additional signal amplification needed before feedback amplifier\n",
+      "\n",
+      "#Results\n",
+      "print\"feedback gain is\",beta\n",
+      "print\"signal input to the overall system is\",s"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "feedback gain is 0.09\n",
+        "signal input to the overall system is 10.0\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 6.2,Page number 332"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "w2=10**4.             #corner frequency(rad/s)  \n",
+      "w2new=10**5.          #new corner frequency(rad/s)  \n",
+      "Ao=1000.              #high frquency response        \n",
+      "\n",
+      "#Calculations\n",
+      "beta=((w2new/w2)-1)/Ao #feedback factor\n",
+      "Anew=Ao/(1+beta*Ao)   #overall gain of amplifier from formula w2new=w2(1+beta*Ao)\n",
+      "p=w2*Ao               #gain bandwidth product without feedback from formula Anew=Ao/1+beta*Ao\n",
+      "pnew=Anew*w2new       #gain bandwidth product with feedback\n",
+      "\n",
+      "#Results\n",
+      "print\"beta is\",beta\n",
+      "print\"overall gain is\",Anew\n",
+      "print\"gain-bandwidth products with and without feedback are\",p,\"and\",pnew,\"resp.\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "beta is 0.009\n",
+        "overall gain is 100.0\n",
+        "gain-bandwidth products with and without feedback are 10000000.0 and 10000000.0 resp.\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 6.3,Page number 333"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "A=100.                               #high frquency response        \n",
+      "Af=100                               #gain     \n",
+      "A1=A**2                              #forward gain\n",
+      "A1new=50                             #gain reduces to 50%  \n",
+      "\n",
+      "#Calculations\n",
+      "beta=((A1/Af)-1)/A1                  #feedback factor\n",
+      "Afnew=A1new**2/(1+beta*A1new**2)     #new value of A\n",
+      "g=Af-Afnew                           #reduction in overall gain\n",
+      "\n",
+      "#Results\n",
+      "print\"% change in gain of feedback unit is\",round(g,2)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "% change in gain of feedback unit is 2.91\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 6.4,Page number 337"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "beta=0.008                   #positive gain \n",
+      "\n",
+      "#Calculations\n",
+      "Ao=-(8/beta)**(1/3)          #A=Ao/2,so beta(A^3)=-1\n",
+      "\n",
+      "#Results\n",
+      "print\"% change in gain of feedback unit is\",round(Ao/1E-1)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "% change in gain of feedback unit is -10.0\n"
+       ]
+      }
+     ],
+     "prompt_number": 14
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 6.5Page number 337"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import cmath\n",
+      "from math import pi,degrees\n",
+      "\n",
+      "#Variable declarations\n",
+      "A = complex(0,60)                  #amplifier\n",
+      "B = complex(0,30)                  #amplifier\n",
+      "AB = A*B\n",
+      "C = (1+A)/AB                       #condition for oscillation\n",
+      "phi = cmath.phase(C)               #phase\n",
+      "\n",
+      "#Result\n",
+      "print \"C =\",round(abs(C),4),\"with phase =\",round(degrees(phi),2)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "C = 0.0333 with phase = -90.95\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 6.7,Page number 347"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Rbb=8*10**3                  #base resistance(k ohms)\n",
+      "eta=0.7                     #efficiency\n",
+      "R1=0.2                      #R1(k ohms)\n",
+      "Rt=40*10**3                 #Rt(ohms)\n",
+      "Ct=0.12*10**-6              #capacitance(F)\n",
+      "Vv=2                        #capacitor is charged to voltage(V)\n",
+      "Iv=10*10**-3                #current to capacitor(A)\n",
+      "Ip=10*10**-3                 #peak current(A)\n",
+      "Vd=0.7                      #diode voltage(V)\n",
+      "V=12.                        #voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Rb1=eta*Rbb    #base resistance(ohms) \n",
+      "Rb2=Rbb-Rb1             #base resistance(ohms)\n",
+      "\n",
+      "#Part b\n",
+      "Vp=Vd+((Rb1+R1)*V/(Rbb+R1))    #peak voltage(V)\n",
+      "\n",
+      "#Part c\n",
+      "Rtmin=(V-Vv)/Iv          #Rt minimum(k ohms)        \n",
+      "Rtmax=(V-Vp)/Ip          #Rt minimum(k ohms)  \n",
+      "\n",
+      "#Part d\n",
+      "Rb11=.12                #resistance during discharge(ohms)\n",
+      "t1=Rt*Ct*1.27           #charging time(mS)\n",
+      "t2=(Rb11+R1)*Ct*1.52    #discharging time(uS)\n",
+      "T=t1+t2                 #cycle time\n",
+      "foscE=1/T               #oscillations frequency(Hz)\n",
+      "foscA=1/(Rt*Ct*1.2)     #oscillations frequency(Hz)\n",
+      "\n",
+      "#Part e\n",
+      "vR1=(R1*V)/(R1+Rbb)             #vR1 at discharging period\n",
+      "vR1d=(R1*(Vp-Vd))/(R1+Rb11)      #vR1 at discharging period\n",
+      "\n",
+      "#Results\n",
+      "print\"Rb1 and Rb2 are\",round((Rb1/1E+3),1),\"k ohms and\",round((Rb2/1E+3),1),\"k ohms resp.\"\n",
+      "print\"Vp is\",round(Vp,1),\"V\"\n",
+      "print\"Rtmin is\",round(Rtmin/1E+3),\",k ohms and Rtmax is\",round(Rtmax/1E+1),\"k ohms,hence Rt is in the range\"\n",
+      "print\"foscE is\",round(foscE),\"Hz and foscA is\",round(foscA),\"Hz\"\n",
+      "print\"vR1 is\",round((vR1/1E-3),3),\"and vRd1 is\",round(vR1d,2),\"V (range of Rt is wrong in the book)\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Rb1 and Rb2 are 5.6 k ohms and 2.4 k ohms resp.\n",
+        "Vp is 9.1 V\n",
+        "Rtmin is 1.0 ,k ohms and Rtmax is 29.0 k ohms,hence Rt is in the range\n",
+        "foscE is 164.0 Hz and foscA is 174.0 Hz\n",
+        "vR1 is 0.3 and vRd1 is 5.25 V (range of Rt is wrong in the book)\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 6.8,Page number 350"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "A=1500                         #voltage gain\n",
+      "beta=1/25.                     #current gain \n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Af=A/(1+A*beta)                 #voltage gain with feedback\n",
+      "\n",
+      "#Part b\n",
+      "g=0.1                        #amplifier gain changes by 10%=0.1\n",
+      "gf=g/(1+A*beta)              #% by which its gain in feedback mode changes dAf/Af\n",
+      "\n",
+      "#Results\n",
+      "print\"Amplifier gain with feedback is\",round(Af,1)\n",
+      "print\"% by which gain in feedback changes is\",round((gf/1E-2),3),\"%\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Amplifier gain with feedback is 24.6\n",
+        "% by which gain in feedback changes is 0.164 %\n"
+       ]
+      }
+     ],
+     "prompt_number": 24
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 6.9,Page number 351"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "A=500                      #voltage gain\n",
+      "beta=1/20.                 #current gain\n",
+      "Ro=50*10**3                #output resistance(ohms) \n",
+      "Ri=1.5*10**3               #input resistance(ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Af=A/(1+A*beta)            #voltage gain with feedback   \n",
+      "\n",
+      "#Part b\n",
+      "Rif=Ri*(1+(A*beta))         #input resistance(k ohms)\n",
+      "Rof=Ro/(1+A*beta)           #output resistance(k ohms)\n",
+      "\n",
+      "#Results\n",
+      "print\"Amplifier gain is\",round(Af,2)\n",
+      "print\"input resistance is\",round(Rif/1E+3),\"K ohms and output resistance is\",round((Rof/1E+2),2),\"Kohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Amplifier gain is 19.23\n",
+        "input resistance is 39.0 K ohms and output resistance is 19.23 Kohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 6.10,Page number 351"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Ro=50*10**3                 #output resistance(ohms)\n",
+      "Rd=10*10**3                 #drain resistance(ohms)\n",
+      "R1=800*10**3                #resistance(ohms)\n",
+      "R2=200*10**3                #resistance(ohms)\n",
+      "gm=5500*10**-6              #transconduuctance(us)\n",
+      "\n",
+      "#Calculations\n",
+      "r=(Rd*Ro)/(Rd+Ro)            #Rd||Ro\n",
+      "R=R1+R2                      #combined resistance of R1 and R2\n",
+      "Rl=(R*r)/(R+r)               #load resistance(ohms)\n",
+      "A=-gm*Rl                     #voltage gain without feedback\n",
+      "beta=R2/(R1+R2)              #current gain \n",
+      "Af=A/(1+A*beta)              #voltage gain with feedback\n",
+      "\n",
+      "#Results\n",
+      "print\"Amplifier gain with feedback is\",round((Af/1E+1),1),\"and without feedback is\",A"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Amplifier gain with feedback is -4.5 and without feedback is -45.452\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 6.11,Page number 352"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Re=1.25*10**3              #emitter resistance(ohms)\n",
+      "Rc=4.8*10**3                #collector resistance(ohms)\n",
+      "Rb=800*10**3               #base resistance(ohms)     \n",
+      "rpi=900                    #dynamic resistance(ohms)\n",
+      "Vcc=16                     #supply voltage(V)\n",
+      "beta=100.                  #current gain \n",
+      "\n",
+      "#Calculations\n",
+      "A=-(beta/rpi)             #amplifier voltage gain  \n",
+      "B=-Re                     \n",
+      "V=(A*Rc)/(1+B*A)          #V=Vo/Vs\n",
+      "   \n",
+      "#Results\n",
+      "print\"Amplifier voltage gain is\",round(V,1)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Amplifier voltage gain is -3.8\n"
+       ]
+      }
+     ],
+     "prompt_number": 58
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 6.12,Page number 352"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      " import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "C1=800*10**-9                   #capacitance(F)\n",
+      "C2=2400*10**-9                  #capacitance(F)\n",
+      "L=50*10**-6                     #inductance(H)\n",
+      "\n",
+      "#Calculations\n",
+      "Ceq=(C1*C2)/(C1+C2)                #equivalent capacitance(F)\n",
+      "fo=1/(2*math.pi*math.sqrt(L*Ceq))  #output frequency(Hz)\n",
+      "\n",
+      "#Results\n",
+      "print\"the oscillation frequency is\",round((fo/1E+3),2),\"KHz\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "the oscillation frequency is 29.06 KHz\n"
+       ]
+      }
+     ],
+     "prompt_number": 8
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 6.13,Page number 353"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "C=200*10**-9               #capacitance(F)\n",
+      "Lrcf=0.5*10**-3            #shunt across L2\n",
+      "L1=800*10**-6              #inductance(H)\n",
+      "L2=800*10**-6              #inductance(H)\n",
+      "M=200*10**-6              \n",
+      "\n",
+      "#Calculations\n",
+      "L21=(L2*Lrcf)/(L2+Lrcf)                  #effective value of L2(uH)\n",
+      "Leq=L1+L21+2*M                           #equivalent inductance(H)\n",
+      "fo=1/(2*math.pi*math.sqrt(Leq*C))        #output frequency(Hz)\n",
+      "\n",
+      "#Results\n",
+      "print\"the oscillation frequency is\",round((fo/1E+3),2),\"KHz\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "the oscillation frequency is 9.17 KHz\n"
+       ]
+      }
+     ],
+     "prompt_number": 13
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Electronics_Devices_And_Circuits/chapter1.ipynb b/Electronics_Devices_And_Circuits/chapter1.ipynb
new file mode 100755
index 00000000..f90f9ea5
--- /dev/null
+++ b/Electronics_Devices_And_Circuits/chapter1.ipynb
@@ -0,0 +1,1579 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:24516babfb49304af52e8c58a067e6fa8878e66215919fc53473493b16a99fdf"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "Chapter 1: SEMICONDUCTORS,DIODE AND DIODE CIRCUITS"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.1, Page number 5"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "A=6.022*10**23     #avagadro's number(/m^3)\n",
+      "d=2.7*10**6        #density of aluminium conductor(g/m^3)\n",
+      "a=26.98            # atomic weight aluminium conductor(g/g-atom)\n",
+      "D=10**4.           #current density(A/m^2)\n",
+      "e=1.6*10**-19      #electronic charge(C)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "n=A*d/a            #number of atoms(n/m^3)\n",
+      "\n",
+      "#Part b\n",
+      "u=D/(n*e)          #drift velocity (m/s)\n",
+      "\n",
+      "#Results\n",
+      "print \"number of atoms per cubic meter is \",round(n/1e+28,3),\"*10^28 /m^3\"\n",
+      "print \"drift velocity is\",round(u/1e-6,2),\"*10^-6 m/s\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "number of atoms per cubic meter is  6.026 *10^28 /m^3\n",
+        "drift velocity is 1.04 *10^-6 m/s\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.2, Page number 6"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "n=10**23        #number of electrons(n/m^3)\n",
+      "e=1.6*10**-19   #electronic charge(C) \n",
+      "u=0.4           #mobility(m^2/Vs)           \n",
+      "a=10**-7        #cross sectional area(m^2) \n",
+      "l=15*10**-2     #conductor length(m)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "G=n*e*u         #conductivity(S/m)\n",
+      "\n",
+      "#Part b\n",
+      "R=l/(a*G)       #resistance(ohm)\n",
+      "\n",
+      "#Results\n",
+      "print\"conductivity of the conductor is\",round((G/1E+3),1),\"*10**3 S/m\"\n",
+      "print\"resistance of the conductor is\",round(R,1),\"ohm\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "conductivity of the conductor is 6.4 *10**3 S/m\n",
+        "resistance of the conductor is 234.4 ohm\n"
+       ]
+      }
+     ],
+     "prompt_number": 27
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.3, Page number 9"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "A=6.022*10**23   #avagadro's number\n",
+      "d=5.32*10**6     #density of Ge at 300k(g/m^3)\n",
+      "a=72.60          #atomic weight of Ge(g/g-atom)\n",
+      "e=1.6*10**-19    #electronic charge(C)\n",
+      "ni=2.4*10**19    #intrinsic concentration(electron-hole pairs/m^3)\n",
+      "un=0.39          #electron mobility(m^2/V.s)\n",
+      "up=0.19          #hole mobility(m^2/V.s)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "nA=A*d/a         #number of atoms(nA/m^3)using avagadro's law\n",
+      "x=nA/ni          #Germanium atoms/electron hole pair\n",
+      "\n",
+      "#Part b\n",
+      "g=(un+up)*e*ni   #intrinsic conductivity(S/m)\n",
+      "r=1/g            #intrinsic resistivity(ohm.m)\n",
+      "\n",
+      "#Results\n",
+      "print\"the relative concentration of Ge and electron hole pairs is\",round((x/1E9),2),\"*10^9 atoms/electron-hole pair\"\n",
+      "print\"the intrinsic resistivity of Ge is\",round(r,3),\"ohm.m\" "
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "the relative concentration of Ge and electron hole pairs is 1.84 *10^9 atoms/electron-hole pair\n",
+        "the intrinsic resistivity of Ge is 0.449 ohm.m\n"
+       ]
+      }
+     ],
+     "prompt_number": 6
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.4,Page number 13"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "ni=1.5*10**16    #intrinsic concentration(electron-hole pairs/m^3)\n",
+      "n=4.99*10**28    #number of Si atoms(atoms/m^3)\n",
+      "un=0.13          #electron mobility(m^2/V.s)\n",
+      "up=0.05          #hole mobility(m^2/V.s)\n",
+      "e=1.6*10**-19    #electronic charge(c)\n",
+      "\n",
+      "#Calculation\n",
+      "#Part a\n",
+      "g=e*ni*(un+up)  #intrinsic conductivity(S/m)\n",
+      "r=1/g           #interinsic resistivity(ohm.m)\n",
+      "Nd=n/10**8      #doped silicon(atoms/m^3)=nn,majority carriers\n",
+      "pn=ni**2/Nd     #minority carrier density(holes/m^3)\n",
+      "\n",
+      "#Part b\n",
+      "k=e*un*Nd    #conductivity(S/m)\n",
+      "             #using Nd in place of nn as Nd=nn\n",
+      "rho=1/k      #resistivity(ohm.m)\n",
+      "\n",
+      "#Results\n",
+      "print\"the minority carrier density of Si is\",round(pn/1e+11,2),\"*10^11 holes/m^3\"\n",
+      "print\"the resistivity of Si is\",round((rho/1E-2),2),\"*10**-2 ohm.m\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "the minority carrier density of Si is 4.51 *10^11 holes/m^3\n",
+        "the resistivity of Si is 9.63 *10**-2 ohm.m\n"
+       ]
+      }
+     ],
+     "prompt_number": 8
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.5,Page number 17"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Vo=0.7                  #contact potential(V)\n",
+      "Vf=0.4                  #forward biasing voltage(V)    \n",
+      "\n",
+      "#Calculation\n",
+      "x=math.exp(-20*(Vo-Vf))/math.exp(-20*Vo)   #increase in probability of majority carriers\n",
+      "\n",
+      "#Result\n",
+      "print\"increase in probability of majority carriers is\",round(x),\"times\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "increase in probability of majority carriers is 2981.0 times\n"
+       ]
+      }
+     ],
+     "prompt_number": 7
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.6,Page number 18"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "I=10    #Ge diode carries current(mA)\n",
+      "V=0.2   #forward bias voltage(V)\n",
+      "\n",
+      "#Calculation\n",
+      "#Part a\n",
+      "Is=I/(math.expm1(40*V)-1)      #reverse current(mA)\n",
+      "\n",
+      "#part b\n",
+      "I1=1*10**-3                     #current(mA)                     \n",
+      "V1=(math.log((I1/Is)+1))/40      #voltage(V)\n",
+      "I2=100*10**-3                  #current(mA) \n",
+      "V2=(math.log((I2/Is)+1))/40     #voltage(V) \n",
+      "\n",
+      "#Part c\n",
+      "Is1=4*Is                 #reverse saturation current doubles for every 10 degree celcius temp rise,so for 20 degree rise it will be 4 timese/   \n",
+      "x=37.44                  #let x=e/kT\n",
+      "I3=Is1*(math.expm1(x*V)) #current when temp doubles(mA)\n",
+      "\n",
+      "#Results\n",
+      "print\"the reverse current is\",round(Is/1e-3,3),\"mA\"  #incorrect units given in the textbook\n",
+      "print\"bias voltages are\",round(V1,3),\"V and\", round(V2,3),\"V resp\"\n",
+      "print\"Is at 20 degree is\",round(Is1/1e-3,2),\"uA and diode current at 0.2 V is\",round(I3,2),\"mA\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "the reverse current is 3.357 mA\n",
+        "bias voltages are 0.007 V and 0.086 V resp\n",
+        "Is at 20 degree is 13.43 uA and diode current at 0.2 V is 23.97 mA\n"
+       ]
+      }
+     ],
+     "prompt_number": 10
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.7,Page number 21"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "V=3.            #Voltage(V)\n",
+      "Req=300.        #total resistance as per circuit(ohm)\n",
+      "Rfa=20           #forward resistance(ohm)    \n",
+      "Vt=0.7          #Thevinine's voltage(V)\n",
+      "Rfb=0            #forward resistance(ohm)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "I=V/Req          #current(A)\n",
+      "\n",
+      "#Part b\n",
+      "Id=(V-Vt)/Req   #diode current(mA)\n",
+      "\n",
+      "#Part c\n",
+      "Rf=20               #forward resistance(ohms) \n",
+      "Id1=(V-Vt)/(Req+Rfa) #diode current(mA)\n",
+      "\n",
+      "#Results\n",
+      "print\"current in this case is\",round(I,2),\"A\"\n",
+      "print\"diode current is\",round((Id/1E-3),2),\"mA\"\n",
+      "print\"diode current is\",round((Id1/1E-3),2),\"mA\"\n"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "current in this case is 0.01 A\n",
+        "diode current is 7.67 mA\n",
+        "diode current is 7.19 mA\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.9,Page number 22"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vx=1.4              #voltage at point X(V) \n",
+      "Vt=0.7              #diode voltage(V)\n",
+      "Vcc=5               #cathode voltage(V)  \n",
+      "R=1                 #circuit resistance(ohm) \n",
+      "Vs=Vx-Vt            #supply voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "I1=(Vcc-Vt-Vs)/R      #current throgh D1(mA) for 0<Vs<0.7\n",
+      "I2=0                  #current through D2 and D3\n",
+      "I1=I2=(Vcc-Vt-Vs)/R   #for Vs>0.7 as D2 and D3 conducts\n",
+      "\n",
+      "#Results\n",
+      "print\"I1 for 0<Vs<0.7 is\",I1,\"mA\"\n",
+      "print\"I2 for 0<Vs<0.7 is\",I2,\"mA\"\n",
+      "print\"I1 and I2 for Vs>0.7 is\",I1,\"mA\" "
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "I1 for 0<Vs<0.7 is 3.6 mA\n",
+        "I2 for 0<Vs<0.7 is 0 mA\n",
+        "I1 and I2 for Vs>0.7 is 3.6 mA\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.11,Page number 23"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vz=100          #zener voltage(V)\n",
+      "Rz=25           #diode resistance(ohm)\n",
+      "Il=0.05         #load current(A)\n",
+      "Iz=0.01         #zener diode current(A)\n",
+      "Rs=250          #supply resistance(ohm)\n",
+      "\n",
+      "#Calculations\n",
+      "Vl=Vz+(Iz*Rz)     #load voltage(V)\n",
+      "Vs=Vl+(Il+Iz)*Rs  #supply voltage(V)\n",
+      "VL=Vl*1.01        #increase in Vl(V)\n",
+      "IZ=(VL-Vz)/Rz     #increase in zener current\n",
+      "VS=Vl+(Il+IZ)*Rs  #increase in supply voltage(V)\n",
+      "Vss=(VS-Vs)/Vs    #%increase in supply voltage(V)\n",
+      "P=Il*VL           #power consumed(W) \n",
+      "\n",
+      "#Results\n",
+      "print\"load voltage is\",Vl,\"V\"\n",
+      "print\"supply voltage is\",Vs,\"V\"\n",
+      "print\"increase in supply voltage is\",VS,\"V\"\n",
+      "print\"power consumed is\",round(P,2),\"W\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        " load voltage is 100.25 V\n",
+        "supply voltage is 115.25 V\n",
+        "increase in supply voltage is 125.275 V\n",
+        "power consumed is 5.06 W\n"
+       ]
+      }
+     ],
+     "prompt_number": 8
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.12,Page number 25"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vbb=5           #bias voltage(V)\n",
+      "Rl=1            #resistance(ohm)\n",
+      "Id=4.4          #from the figure(mA)\n",
+      "\n",
+      "#Part a\n",
+      "i=Vbb/Rl        #load line intercepts the Id axis at i(mA)\n",
+      "Vl=Id*Rl        #load voltage(V)\n",
+      "\n",
+      "#Part b\n",
+      "Vd=Vbb-Vl       #diode voltage(V)\n",
+      "P=Vd*Id         #power absorbed in diode(mW)\n",
+      "\n",
+      "#Part c        \n",
+      "Ida=1.42         #diode current(mA)for 2V\n",
+      "Idb=7.35         #diode current(mA)for 8V\n",
+      "\n",
+      "#Part d\n",
+      "Idc=8.7         #diode current(mA)for Rl=0.5k ohm \n",
+      "Idd=2.2         #diode current(mA)for Rl=2k ohm\n",
+      "\n",
+      "#Results\n",
+      "print\"diode current is\",Id,\"mA and voltage across the load is\",Vl,\"V\"\n",
+      "print\"power absorbed in diode is\",P,\"mW\"\n",
+      "print\"diode current for Vbb=2V is\",Ida,\"mA\",\"and for Vbb=8V is\",Idb,\"mA\"\n",
+      "print\"diode current for Rl=0.5kohm is\",Idc,\"mA\",\"and for Rl=2kohm is\",Idd,\"mA\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "diode current is 4.4 mA and voltage across the load is 4.4 V\n",
+        "power absorbed in diode is 2.64 mW\n",
+        "diode current for Vbb=2V is 1.42 mA and for Vbb=8V is 7.35 mA\n",
+        "diode current for Rl=0.5kohm is 8.7 mA and for Rl=2kohm is 2.2 mA\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.13,Page number 38"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "T=300             #temperature(k)\n",
+      "Ig=100*10**-3     #current(mA)\n",
+      "Is=1*10**-9       #current(nA)\n",
+      "x=0.0259          #x=kT/e\n",
+      "\n",
+      "#Calculations\n",
+      "Voc=x*math.log(Ig/Is+1)     #as Voc=kT/e*ln((Ig/Is)+1) where ln((Ig/Is)+1)=18.42 after solving \n",
+      "Isc=Ig\n",
+      "\n",
+      "#Result\n",
+      "print\"for a solar cell Voc is\",round(Voc,3),\"V and Isc is\",round(Isc/1E-3),\"mA\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "for a solar cell Voc is 0.477 V and Isc is 100.0 mA\n"
+       ]
+      }
+     ],
+     "prompt_number": 11
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.14,Page number 38"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Idc=0.1           #dc current(A)\n",
+      "Rf=0.5            #forward resistance(ohms)\n",
+      "Rl=20             #load resistance(ohm)\n",
+      "Rs=1              #secondary resistance of transformer(ohm)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Vdc=Idc*Rl                       #dc voltage(V)\n",
+      "Vm=(math.pi/2)*(Vdc+Idc*(Rs+Rf)) #mean voltage(V)\n",
+      "Vrms=Vm/math.sqrt(2)             #rms value of voltage(V)   \n",
+      "\n",
+      "#Part b\n",
+      "Pdc=Idc**2*Rl                  #dc power supplied to the load\n",
+      "\n",
+      "#Part c\n",
+      "PIV=2*Vm                       #PIV rating for each diode(V)\n",
+      "\n",
+      "#Part d\n",
+      "Im=(math.pi/2)*Idc            #peak value of current(mA)\n",
+      "Irms=Im/math.sqrt(2)          #rms calue of current(A)\n",
+      "Pac=Irms**2*(Rs+Rf+Rl)        #ac power input(W)\n",
+      "\n",
+      "#Part e\n",
+      "eta=(Pdc/Pac)*100             #conversion efficiency\n",
+      "\n",
+      "#Part f\n",
+      "Vr=((Rs+Rf)/Rl)*100           #voltage regulation(V)\n",
+      "\n",
+      "#results\n",
+      "print\"rms value of voltage is\",round(Vrms,2),\"V\"\n",
+      "print\"dc power supplied to load is\",Pdc,\"W\"\n",
+      "print\"PIV rating for each diode\",round(PIV,2),\"V\"\n",
+      "print\"ac input power is\",round(Pac,3),\"W\"\n",
+      "print\"conversion efficiency\",round(eta,1),\"%\"\n",
+      "print\"voltage regulation\",Vr,\"%\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "rms value of voltage is 2.39 V\n",
+        "dc power supplied to load is 0.2 W\n",
+        "PIV rating for each diode 6.75 V\n",
+        "ac input power is 0.265 W\n",
+        "conversion efficiency 75.4 %\n",
+        "voltage regulation 7.5 %\n"
+       ]
+      }
+     ],
+     "prompt_number": 19
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.15,Page number 46"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "from scipy import integrate\n",
+      "\n",
+      "#Variable declaration\n",
+      "Vt=1                 \n",
+      "Vl=12\n",
+      "Vm=63.63                      #peak voltage(V) as Vm=sqr root of 2*45\n",
+      "Idc=8.                        #charging current(A)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "theta1=math.degrees(math.asin((Vt+Vl)/Vm))\n",
+      "theta2=180-theta1\n",
+      "Rl=((2*Vm*math.cos(theta1))-(2*(math.pi-2*theta1)*(Vt+Vl)))/(Idc*math.pi)\n",
+      "\n",
+      "#Part b\n",
+      "wt = lambda wt: (((((math.sqrt(2)*45*math.sin(wt))-(Vt+Vl))/Rl)*wt)**2)\n",
+      "integ,err = integrate.quad(wt, theta1 , theta2)\n",
+      "print integ\n",
+      "Irms = (integ/math.pi)**0.5\n",
+      "Pl=Irms**2*Rl               #power loss in resistance(W)\n",
+      "\n",
+      "#Part c\n",
+      "P=Vl*Idc                   #power supplied to battery(W)\n",
+      "\n",
+      "#results\n",
+      "print\"Resistance to be added is\",round(Rl,2),\"Ohms\"\n",
+      "print\"\",Pl\n",
+      "print\"power supplied to battery is\",P,\"W\"\n",
+      "print\"\",Irms  "
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "5703935.44277\n",
+        "Resistance to be added is 24.75 Ohms\n",
+        " 44936628.7032\n",
+        "power supplied to battery is 96.0 W\n",
+        " 1347.44908683\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.16,Page number 47"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Rf=5                    #forward resistance(ohms)\n",
+      "Vo=20                   #output voltage(V)\n",
+      "Rs=10                   #secondary resistance of transformer(ohm)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Idc=0.1                 #dc current(A)                  \n",
+      "Vm=Vo*(math.sqrt(2))    #mean voltage(V)\n",
+      "Vdc=(2*Vm/(math.pi))-Idc*(Rs+2*Rf)  #dc voltage(V)\n",
+      "\n",
+      "#Part b\n",
+      "Idc1=0.2                #full load dc current(A)\n",
+      "Vdc2=((2*(math.sqrt(2))*Vo)/(math.pi))-Idc1*(Rs+2*Rf) #full load dc voltage(V)\n",
+      "Rl=Vdc2/Idc1              #load resistance(ohm)\n",
+      "x=((2*Rf+Rs)/Rl)*100      #% regulation \n",
+      "\n",
+      "#Part c\n",
+      "Idc=0.2                  #dc current(A)\n",
+      "Im=(math.pi)*Idc/2       #peak current(mA)\n",
+      "Ilrms=Im/math.sqrt(2)    #rms current(mA)\n",
+      "Vlrms=Ilrms*Rl           #load rms voltage(V) \n",
+      "\n",
+      "#Part d\n",
+      "Vldc=14                               #load dc voltage(V)\n",
+      "Vlacrms=math.sqrt(Vlrms**2-Vldc**2)   #rms value of ac component(V)\n",
+      "\n",
+      "#Results\n",
+      "print\"dc voltage\",round(Vdc),\"V\"\n",
+      "print\"regulation is\",round(x,2),\"%\"\n",
+      "print\"rms value of output voltage at dc load current is\",round(Vlrms,2),\"V\"\n",
+      "print\"rms value of ac component of voltage\",round(Vlacrms,2),\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "dc voltage 16.0 V\n",
+        "regulation is 28.56 %\n",
+        "rms value of output voltage at dc load current is 15.56 V\n",
+        "rms value of ac component of voltage 6.78 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 6
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.17,Page number 50"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vh=60.           #higher output voltage(V)\n",
+      "Vl=45.           #lower output voltage(V)  \n",
+      "fz=50.           #frequency(Hz)\n",
+      "Vr=15.           #peak to peak ripple voltage(V)\n",
+      "Rl=600.          #resistance(ohms)\n",
+      "     \n",
+      "#Calculations\n",
+      "Vldc=(Vh+Vl)/2   #avg load dc voltage(V) as voltage drops from 60 to 45\n",
+      "Idc=Vldc/Rl      #dc current(A)\n",
+      "T=1/fz           #discharging time(ms)\n",
+      "C=(Idc*T)/Vr     #linear discharge rate(uF)\n",
+      "C1=C*2           #new capacitance(uF)\n",
+      "'''\n",
+      "         CVr(p-p)       234Vr(p-p)*10^3\n",
+      "Idc = -------------- = ---------------    ----(1)\n",
+      "          T                   20\n",
+      "    \n",
+      "      60+[60-Vr(p-p)     120-Vr(p-p)\n",
+      "Idc = --------------- = ------------*1000   ----(2)\n",
+      "         2Rl               2*600\n",
+      "         \n",
+      "Equating equations 1 & 2, we get,    \n",
+      "'''\n",
+      "\n",
+      "Vr1 = (20*120*1000)/(1200*254)\n",
+      "Idc1=(Vh-(Vr1/2))/Rl               #dc load current(mA)\n",
+      "\n",
+      "#Results\n",
+      "print\"value of capacitance is\",round(C/1E-6),\"uF\" \n",
+      "print\"Vr1 is\",Vr1,\"V\" \n",
+      "print\"dc load current Idc is\",round(Idc1/1E-3),\"mA\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "value of capacitance is 117.0 uF\n",
+        "Vr1 is 7 V\n",
+        "dc load current Idc is 95.0 mA\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.18,Page number 51"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Vdc=30                          #dc voltage(V)\n",
+      "V1=220                          #source voltage(V)\n",
+      "f=50                            #frequency(Hz)\n",
+      "Rl=1000                         #load resistance(k ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "C=100/f*Rl                      #as Vdc/Vr=100\n",
+      "Vm=Vdc+(Vr/2)                   #peak voltage(V)\n",
+      "V2=Vm/(math.sqrt(2))            #secondary voltage(V)\n",
+      "r=V1/V2                         #transformer turn ratio\n",
+      "\n",
+      "#Results\n",
+      "print\"capacitor filtor is\",C,\"uF\"\n",
+      "print\"transformer turn ratio is\",round(r,2),\"\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "capacitor filtor is 2000 uF\n",
+        "transformer turn ratio is 10.37 \n"
+       ]
+      }
+     ],
+     "prompt_number": 37
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.19,Page number 52"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Idc=60*10**-3                      #dc current(A)\n",
+      "Vm=60                              #peak volage(V)\n",
+      "f=50                               #frequency(Hz)\n",
+      "C=120*10**-6                       #capacitance(F)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Vrms=Idc/(4*(math.sqrt(3))*f*C*Vm) #rms voltage(V)\n",
+      "Vr=2*(math.sqrt(3))*Vrms           #ripple factor(V)\n",
+      "\n",
+      "#Part b\n",
+      "Vdc=Vm-(Vr/2)                      #by simplifying\n",
+      "\n",
+      "#Part c\n",
+      "r=(Vrms/Vdc)*100                   #ripple factor\n",
+      "\n",
+      "#Results\n",
+      "print\"ripple factor is\",round(Vr,3),\"Vdc\"\n",
+      "print\"dc voltage is\",round(Vdc),\"V\"\n",
+      "print\"ripple factor\",round(r,4),\"%\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "ripple factor is 0.083 Vdc\n",
+        "dc voltage is 60.0 V\n",
+        "ripple factor 0.0401 %\n"
+       ]
+      }
+     ],
+     "prompt_number": 8
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.20,Page number 54"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "'''     200*1.141      4\n",
+      "v1(t)=-------------(1- - cos628t) \n",
+      "          3.14         3\n",
+      "       200*1.141      800*1.141 \n",
+      "v2(t)=----------- - ------------  cos(628t+<(V2/V1))\n",
+      "         3.14          3*3.14\n",
+      "\n",
+      "V2/V1|w=0 =0.8;V2/V1|w=628 =6.43*10^-4 <V2/V1|w=628 =180\n",
+      "v2(t)=72.02+0.0538 cos628t\n",
+      "'''\n",
+      "#Part b\n",
+      "vrms=0.0538\n",
+      "vdc=math.sqrt(2)*72.02\n",
+      "r=vrms/vdc\n",
+      "\n",
+      "#Results\n",
+      "print\"ripple factor is\",round((r/1E-4),2),\"*10**-4\"\n"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "ripple factor is 5.28 *10**-4\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.24,Page number 61"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Vz=2                    #zener voltage(V)\n",
+      "r1=10                   #resistance after reducing circuit by thevinin(ohms)\n",
+      "r2=20                   #resistance after reducing circuit by thevinin(ohms)\n",
+      "V1=7.5                  #voltage after circuit reduction(V)\n",
+      "V2=15                   #voltage after circuit reduction(V)\n",
+      "Rz=100/3                #zener resistance(ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "Vab=V2-(((V2-V1)/(r1+r2))*r2)         #thevinin voltage at ab(V)\n",
+      "Rth=(Vab*r2)/(Vab+r2)                 #thevinin resistance at ab(ohms)\n",
+      "Vd=Vab-Vz                             #diode voltage(V)\n",
+      "Id=Vd/(Rth+Rz)                        #diode current(A)\n",
+      "\n",
+      "#Results\n",
+      "print\"diode current is\",round(Id,2),\"A\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "diode current is 0.2 A\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.25,Page number 61"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vd=0.7                      #diode voltage(V)\n",
+      "Ro=18                       #output resistance(k ohms)\n",
+      "R1=2                        #diode1 resistance(k ohms)\n",
+      "R2=2                        #diode2 resistance(k ohms) \n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "V1=10                       #voltage to D1(V)\n",
+      "V2=0                        #voltage to D2(V)\n",
+      "Io=(V1-Vd)/(R1+Ro)          #output current(mA)   \n",
+      "Vo=Io*Ro                    #output voltage(V)\n",
+      "\n",
+      "#Part b\n",
+      "V1=5                        #voltage to D1(V)\n",
+      "V2=0                        #voltage to D2(V)\n",
+      "Io=(V1-Vd)/(R1+Ro)          #output current(mA)   \n",
+      "Vo1=Io*Ro                   #output voltage(V)\n",
+      "\n",
+      "#Part c\n",
+      "V1=10                      #voltage to D1(V)\n",
+      "V2=5                       #voltage to D2(V)\n",
+      "Vo=8.37                    #as D1 only conducts,so,Vo is same as in part a\n",
+      "Vd1=V2-Vo                  #assume D1 conducts\n",
+      "Vo2=8.37                   #D2 does not conduct as as Vd1 is negative\n",
+      "\n",
+      "#Part d\n",
+      "V1=V2=5                  #voltage to D1 and D2(V) \n",
+      "Id1=(V1-Vd-Vo)/2         #diode1 current(mA)   \n",
+      "Io=Vo/Ro                 #output current(mA)   \n",
+      "Vo3=(Ro*(V1-Vd))/(Ro+1)  #output voltage(V)\n",
+      "\n",
+      "print\"a)output voltage is\",Vo,\"V\"\n",
+      "print\"b)output voltage is\",Vo1,\"V\"\n",
+      "print\"c)output voltage is\",Vo2,\"V\"\n",
+      "print\"d)output voltage is\",round(Vo3,2),\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)output voltage is 8.37 V\n",
+        "b)output voltage is 3.87 V\n",
+        "c)output voltage is 8.37 V\n",
+        "d)output voltage is 4.07 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 71
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.26,Page number 62"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vs=10.                       #supply voltage(V)  \n",
+      "Rs=1                         #supply resistane(ohm)\n",
+      "Vl=10.                       #load voltage(V)\n",
+      "Vi=50.                       #nput voltage(V)\n",
+      "Iz=32                        #zener diode current(mA)\n",
+      "Is=40                        #supply current(mA) \n",
+      "\n",
+      "#Calculations\n",
+      "#Part a (Rl is min when Iz=0)  \n",
+      "Is=(Vi-Vs)/Rs               #source current(mA)       \n",
+      "Rlmin=Vl/(Vi-Vs)            #load resistance minimum(ohm) \n",
+      "\n",
+      "#Part b(Rl is maximum when Iz=32 mA)  \n",
+      "Il=(Is-Iz)*10**-3          #load current(A) \n",
+      "Rlmax=Vl/Il                #maximum load resistance(k ohms)\n",
+      "P=Vl*Iz                    #max diode wattage consumed(mW)\n",
+      "\n",
+      "#Results\n",
+      "print\"Range of Rl is\",round((Rlmin/1E-3),3),\"ohm\",\"to\", round((Rlmax/1E+3),2),\"k ohm\" \n",
+      "print \"Il = \",(Il/1E-3),\"*10**-3 A\"\n",
+      "print\"max power consumed is\",P,\"mW\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Range of Rl is 250.0 ohm to 1.25 k ohm\n",
+        "Il =  8.0 *10**-3 A\n",
+        "max power consumed is 320.0 mW\n"
+       ]
+      }
+     ],
+     "prompt_number": 12
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.27,Page number 63"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vz=20           #zener voltage(V)\n",
+      "Izmax=50        #maximum zener current(mA)\n",
+      "Rz=0            #zener resistance(ohms)\n",
+      "Rl=2.           #load resistance(ohm)\n",
+      "Vl=20.          #as Vz=Vl(V)\n",
+      "Rs=0.25         #source resistance(k ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Il=Vl/Rl           #load current(mA)      \n",
+      "Vsmin=(Rs+Rl)*Il   #as Iz is floating so Iz=0\n",
+      "\n",
+      "#Part b\n",
+      "Is=Izmax+Il        #source current(mA)   \n",
+      "Vsmax=Vz+(Is*Rs)   #maximum source voltage(V)\n",
+      "\n",
+      "#Results\n",
+      "print\"Vsmin\",round(Vsmin,1),\"V\"\n",
+      "print\"Range of input voltage is\",round(Vsmin,1),\"to\", Vsmax,\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Il is 10.0 mA\n",
+        "Vsmin 22.5 V\n",
+        "Range of input voltage is 22.5 to 35.0 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 6
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.28,Page number 63"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Ilmax=100                #load maximum current(mA)\n",
+      "Ilmin=0                  #load minimum current(mA)\n",
+      "Rz=0.05                  #zener diode resistance(ohms)\n",
+      "Rs=10.                    #source resistance(k ohms)\n",
+      "Vl=16.015                #load voltage(V)\n",
+      "Vl1=16.                  #nominal load voltage(V) \n",
+      "Vs=20                    #source voltage(V)\n",
+      "Vz=16                    #zener diode voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "#Case 1 (i)\n",
+      "Iz=(Vl-Vl1)/Rz           #zener current(mA)\n",
+      "Is=Iz+Ilmax              #supply current(A)\n",
+      "\n",
+      "#Case 1 (ii)\n",
+      "Is1=(Vs-Vz)/(Rs+Rz)           #supply current(mA)\n",
+      "Vl2=Vl1+(Is1*Rz)              #voltage(V)  \n",
+      "Vr=((Vl2-Vl)/Vl1)*100        #voltage regulation\n",
+      "\n",
+      "#Case 2 (i)\n",
+      "Vs=18                        #supply voltage(V)\n",
+      "Ilmax=0.1                    #load current max(A)\n",
+      "Vl=16.005                    #load voltage(V)\n",
+      "Iz=(Vl-Vl1)/Rz               #zener current(mA)\n",
+      "Is2=Ilmax+Iz                 #supply current(A)\n",
+      "\n",
+      "#Case 2 (ii)\n",
+      "Ilmin=0\n",
+      "Iz1=(Vs-Vl1)/(Rs+Rz)        #minimum diode current(mA) \n",
+      "Vl=Vl1+(Iz*Rz)              #load voltage at Ilmin(V)          \n",
+      "\n",
+      "#Part a\n",
+      "#Variable declaration\n",
+      "Is=0.4                  #supply current(A)\n",
+      "Vs=20                    #supply voltage(V)   \n",
+      "Vl=16.015               #load voltage(V)\n",
+      "Iz=0.3                   #zener current(mA)\n",
+      "\n",
+      "#Calculations\n",
+      "P=Is**2*Rs               #power dissipated by Rs(W)\n",
+      "\n",
+      "#Part b\n",
+      "Pd=Vl*Iz                  #power dissipated(W)\n",
+      "Po=(Vs**2)/Rs             #output power(W)\n",
+      "\n",
+      "print\"maximum power dissipated by Rs is\",P,\"W\"\n",
+      "print\"maximum power dissipated by diode is\",round(Pd,3),\"W\"\n",
+      "print\"minimum diode current is\",round(Iz1,3),\"A\"\n",
+      "print\"voltage regulation is\",round(Vr,2),\"%\"\n",
+      "print\"output shorted will be\",Po,\"W\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "maximum power dissipated by Rs is 1.6 W\n",
+        "maximum power dissipated by diode is 4.804 W\n",
+        "minimum diode current is 0.199 A\n",
+        "voltage regulation is 0.03 %\n",
+        "output shorted will be 40.0 W\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.29,Page number 65"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Vrms=20                   #secondary voltage(V)\n",
+      "Rs=10                     #Winding resistance(ohm)\n",
+      "Rf=5                      #diode has forward resistance(ohms)\n",
+      "Idc=2*10**-3              #load current(mA)     \n",
+      "\n",
+      "#Calculations\n",
+      "#Part a \n",
+      "Vdc=(Vrms*(math.sqrt(2)))/(math.pi)       #no load Vdc\n",
+      "\n",
+      "#Part b \n",
+      "Vldc=Vdc-(Idc*(Rs+Rf))                    #dc output voltage when load is 20mA\n",
+      "\n",
+      "#Part c\n",
+      "Rl=Vldc/Idc                                #load resistance(ohms)\n",
+      "r=((Rs+Rf)/Rl)*100                         #percentage regulation(%)\n",
+      "\n",
+      "#Part d\n",
+      "Im=Idc*(math.pi)                           #peak current(mA)\n",
+      "Ilrms=Im/2                                 #rms load current(mA) \n",
+      "Vlrms=Ilrms*Rl                             #rms load voltage(V)    \n",
+      "Vlrmsac=math.sqrt((Vlrms**2)-(Vldc**2))    #Ripple voltage rms(V)\n",
+      "f=50*2                                     #rippLe frequency(Hz)\n",
+      "\n",
+      "#Part e\n",
+      "eta=(((2*(math.pi))**2)/(1+((Rs+Rf)/Rl)))*100  #efficiency\n",
+      "\n",
+      "#Part f\n",
+      "PIV=Vm=Vrms*(math.sqrt(2))                     #peak inverse voltage(V)   \n",
+      "\n",
+      "#Results\n",
+      "print\"no load dc voltage is\",round(Vdc),\"V\" \n",
+      "print\"dc output voltage when the load is drawing 20 mA is\",round(Vldc,2),\"V\"\n",
+      "print\"percentage regulation at this load is\",round((r/1E-1),2),\"%\"\n",
+      "print\"ripple voltage rms is\",round(Vlrmsac,2),\"V and ripple frequency is\",f,\"Hz\"\n",
+      "print\"power conversion efficiency is\",round((eta/1E+2),1),\"%\"\n",
+      "print\"PIV is\",round(PIV),\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "no load dc voltage is 9.0 V\n",
+        "dc output voltage when the load is drawing 20 mA is 8.97 V\n",
+        "percentage regulation at this load is 3.34 %\n",
+        "ripple voltage rms is 10.87 V and ripple frequency is 100 Hz\n",
+        "power conversion efficiency is 39.3 %\n",
+        "PIV is 28.0 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 12
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.30,Page number 66"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Vl=24                       #battery voltage(V)\n",
+      "Vm=60*(math.sqrt(2))        #peak voltage(V)\n",
+      "Ip=2.5                      #peak current(A)\n",
+      "c=20                        #charge(Ah)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "theta=math.asin(Vl/Vm)     #angle at which conduction begins\n",
+      "Rs=(Vm-Vl)/Ip              #source resistance(ohms) \n",
+      "\n",
+      "#Part b\n",
+      "Idc=(Vm/(math.pi)*Rs)*(math.cos(theta))-(((math.pi)-(2*theta))/2*math.pi)*(Vl/Rs)   #load current(A)\n",
+      "T=c/Idc                                                                             #time to deliver 20Ah(h)\n",
+      "\n",
+      "#Results\n",
+      "print\"resistance connected in series is\",round(Rs,1),\"ohm\"\n",
+      "print\"time required to deliver a charge of 20 Ah is\",round((T/1E-3),1),\"h\" \n",
+      "print\"Idc\",round((Idc/1E+3),2),\"A\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "resistance connected in series is 24.3 ohm\n",
+        "time required to deliver a charge of 20 Ah is 31.9 h\n",
+        "Idc 0.63 A\n"
+       ]
+      }
+     ],
+     "prompt_number": 21
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.32,Page number 67"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "R=25.                #external resistance(ohms)\n",
+      "Vm=200.              #peak value of voltage(V) as vs=200 sinwt\n",
+      "Rf=50.               #forward resistance(ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a \n",
+      "Id=Vm/(2*Rf+R)      #diode current(peak)\n",
+      "\n",
+      "#Part b \n",
+      "Idc=(2*Id)/math.pi    #dc current(A)\n",
+      "\n",
+      "#Part c\n",
+      "PIV=Vm/2               #peak value of voltage across D1\n",
+      "PIVac=100/math.pi      #average value of voltage across D1\n",
+      "\n",
+      "#Part d\n",
+      "Im=Id                  #peak value of current(A)\n",
+      "Irms=Im/(math.sqrt(2)) #rms value of current(A)\n",
+      "\n",
+      "#Results\n",
+      "print\"peak value of current is\",Id,\"A\"\n",
+      "print\"dc currect is\",round(Idc,2),\"A\"\n",
+      "print\"across D1 are peak voltage is\",PIV,\"V and average voltage is\",round(PIVac,1),\"V\"\n",
+      "print\"Irms is\",round(Irms,2),\"A\"\n"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "peak value of current is 1.6 A\n",
+        "dc currect is 1.02 A\n",
+        "across D1 are peak voltage is 100.0 V and average voltage is 31.8 V\n",
+        "Irms is 1.13 A\n"
+       ]
+      }
+     ],
+     "prompt_number": 13
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.33,Page number 67"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "f=50.              #frequency(Hz)\n",
+      "dv=7.              #difference between maximum and minimum(25-18)voltages across the load(V)\n",
+      "Ic=100.            #load current(mA)\n",
+      "\n",
+      "#Calculations\n",
+      "dt=1/(2*f)        #time of discharge(seconds)\n",
+      "C=Ic/(dv/dt)      #capacitance(uF) \n",
+      "\n",
+      "#Results\n",
+      "print\"value of capacitor is\",round((C/1E-3),2),\"uF\" "
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "value of capacitor is 142.86 uF\n"
+       ]
+      }
+     ],
+     "prompt_number": 56
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.34,Page number 68"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Vr=10.                          #peak to peak ripple voltage(V)\n",
+      "Vm=50.                          #peak output voltage(V)  \n",
+      "C=300.                          #Capacitance(uF)\n",
+      "Rl=470.                         #load resistance(ohms)\n",
+      "f=50.                           #frequency(Hz)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a \n",
+      "Vdc=Vm-(Vr/2)                   #dc voltage(V)      \n",
+      "C=Vdc/(f*Vr*Rl)                 #capacitance(mF)\n",
+      "\n",
+      "#Part b\n",
+      "C1=300*10**-6                    #capacitance is increased(uF)\n",
+      "Vr=2*Vm/((2*f*C1*Rl)+1)\n",
+      "Vdc=Vm-Vr/2                     #load voltage ripple(V)\n",
+      "Idc=Vdc/Rl                      #average load current(mA)\n",
+      "\n",
+      "#Results\n",
+      "print\"value of capacitor is\",round((C/1E-6),1),\"mF\" \n",
+      "print\"load voltage ripple is\",round(Vdc,2),\"V and average load current is\",round((Idc/1E-4),1),\"mA\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "value of capacitor is 191.5 mF\n",
+        "load voltage ripple is 46.69 V and average load current is 993.4 mA\n"
+       ]
+      }
+     ],
+     "prompt_number": 14
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.35,Page number 69"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "vo=7.5                  #instantaneous voltage(V)\n",
+      "R1=15                   #resistance(k ohms)\n",
+      "Von=0.5                 #voltage of diode when on(V)\n",
+      "\n",
+      "#Calculations\n",
+      "Rth=(R1*vo)/(R1+vo)                 #equivalent resistance(V)\n",
+      "T=2*(math.pi)/10**4                 #time period(ms)\n",
+      "t1=(math.asin(Von/2.5))/10**4       #timimgs when D1 conducts(ms)\n",
+      "t2=(T/2)-t1\n",
+      "\n",
+      "#Results\n",
+      "print\"time period is\",round((T/1E-3),3),\"ms\"\n",
+      "print\"t1 is\",t1,\"ms\"\n",
+      "print \"t2 is\",round((t2/1E-3),3),\"ms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "time period is 0.628 ms\n",
+        "t1 is 2.0135792079e-05 ms\n",
+        "t2 is 0.294 ms\n"
+       ]
+      }
+     ],
+     "prompt_number": 6
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 1.36,Page number 70"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declarations\n",
+      "v=12                         #output voltage(V)\n",
+      "vm=20.                       #peak voltage(V)\n",
+      "v1=8                         #output voltage(V) for negative half cycle\n",
+      "vm1=20.                      #peak voltage(V) for negative half cycle \n",
+      "\n",
+      "#Calculations\n",
+      "t1=(math.asin(v/vm))/10**4         #for positive half cycle when D1 conducts\n",
+      "t2=(0.1*math.pi)-t1/1e-3           \n",
+      "t3=(math.asin(v1/vm1))/10**4       #for negative half cycle when D2 conducts\n",
+      "t4=(0.1*(math.pi))+t3/1e-3           \n",
+      "t5=(0.2*(math.pi))-t3/1e-3\n",
+      "\n",
+      "#Results\n",
+      "print\"t1 is\",round(t1/1e-3,3),\"ms\"\n",
+      "print\"t2 is\",round(t2,2),\"ms\"\n",
+      "print\"t3 is\",round(t3/1e-3,3),\"ms\"\n",
+      "print\"t4 is\",round(t4,3),\"ms\"\n",
+      "print\"t5 is\",round(t5,3),\"ms\"\n",
+      "print\"vo is\",\"-5.33+6.66*sin(10**4*.15)\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "t1 is 0.064 ms\n",
+        "t2 is 0.25 ms\n",
+        "t3 is 0.041 ms\n",
+        "t4 is 0.355 ms\n",
+        "t5 is 0.587 ms\n",
+        "vo is -5.33+6.66*sin(10**4*.15)\n"
+       ]
+      }
+     ],
+     "prompt_number": 18
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Electronics_Devices_And_Circuits/chapter10.ipynb b/Electronics_Devices_And_Circuits/chapter10.ipynb
new file mode 100755
index 00000000..3c27caf6
--- /dev/null
+++ b/Electronics_Devices_And_Circuits/chapter10.ipynb
@@ -0,0 +1,458 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:9c34cda4904ac6fe0f4810cba9f641b26f332071fb989df77b245e43b46b8b6c"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "Chapter 10 :     Circuit Theory"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 10.1,Page number 477"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "i1=4.           #current through r1(A)      \n",
+      "v3=3            #voltage(V)\n",
+      "v4=8            #voltage(V)\n",
+      "r3=3            #resistance(ohms)\n",
+      "r2=2            #resistance(ohms)\n",
+      "r4=4            #resistance(ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "i3=v3/r3                #current through r3(A)\n",
+      "i4=v4/r4                #current through r4(A)\n",
+      "i2=-(i3+i4-i1)/2        #current through r2(A)\n",
+      "v2=i2*r2                #voltage through r2(V)\n",
+      "\n",
+      "#Result\n",
+      "print\"v2 is\",v2,\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "v2 is 1.0 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 10.2,Page number 478"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "v1=6                #current through r1(A)   \n",
+      "i2=2                #voltage through r3(V)\n",
+      "i3=4                #voltage through r4(V)\n",
+      "r3=2                #resistance(ohms)\n",
+      "v3=3                #voltage through r3(ohms)\n",
+      "r2=2                #resistance(ohms)\n",
+      "r4=3                #resistance(ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "v2=i2*r2                 #voltage through r2(ohms)\n",
+      "v3=i3*r3                 #voltage through r3(ohms)\n",
+      "v4=4*i2+v3-v2-v1         #voltage through r4(ohms)\n",
+      "i4=v4/r4                 #current through r4(A)\n",
+      "\n",
+      "#Result\n",
+      "print\"i4 is\",i4,\"A\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "i4 is 2 A\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 10.3,Page number 481"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import numpy as np\n",
+      "\n",
+      "#Calculations\n",
+      "a=np.array([[7,-3,-4],[-3,6,-2],[-4,-2,11]])  #solving three linear mesh equations\n",
+      "b=np.array([-11,3,25])\n",
+      "x=np.linalg.solve(a,b)\n",
+      "x\n",
+      "v=x[2]-x[1]                                  #voltage across 2mho conductance(V)\n",
+      "\n",
+      "#Results\n",
+      "print\"v is\",v,\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "v is 1.0"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        " V\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 10.4,Page number 483"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import numpy as np\n",
+      "\n",
+      "#Variable declaration\n",
+      "R=20                            #resistance across which voltage is to be calculated(ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "a=np.array([[35,-20],[-20,50]])  #solving two linear mesh equations\n",
+      "b=np.array([50,-100])\n",
+      "x=np.linalg.solve(a,b)\n",
+      "x\n",
+      "i=x[0]-x[1]           #current through 20 ohms resistor(ohms)\n",
+      "V=20*i                #voltage across 20 ohms(V)\n",
+      "\n",
+      "#Results\n",
+      "print\"i is\",round(i,2)\n",
+      "print\"voltage across 20 ohms is\",round(V,1),\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "i is 2.22\n",
+        "voltage across 20 ohms is 44.4 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 10.5,Page number 484"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vs=16.              #source voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part b\n",
+      "I=0                 #current through 10 V\n",
+      "Is=-4*(I-(Vs/32))   #current of current source(A)\n",
+      "\n",
+      "#Part c\n",
+      "Is1=16              #current of current source(A)\n",
+      "I=0                 #current through 10 V\n",
+      "Vs1=(I+(Is1/4))*32  #source voltage(V)\n",
+      "\n",
+      "#Results\n",
+      "print\"Is is\",Is,\"A\"\n",
+      "print\"Vs1 is\",Vs1,\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Is is 2.0 A\n",
+        "Vs1 is 128 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 20
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 10.6,Page number 485"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "V=9                   #voltmeter of voltage(V)\n",
+      "i=9                   #ammeter current of 9V\n",
+      "r1=1                  #resistance(ohms)\n",
+      "r2=3                  #resistance(ohms)\n",
+      "r=5                   #resistance parallel to ammeter(ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "Isc=((i*r)-V)/(r1+r)       #short circuiting a and b and converting current source to a voltage source(A)\n",
+      "Ro=((r+r1)*r2)/((r+r1)+r2) #output resistance(ohms)\n",
+      "\n",
+      "#Results\n",
+      "print\"Isc is\",Isc,\"A\"\n",
+      "print\"Ro is\",Ro,\"ohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Isc is 6 A\n",
+        "Ro is 2 ohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 5
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 10.7,Page number 495"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import cmath\n",
+      "import math\n",
+      "from sympy import *\n",
+      "import sympy\n",
+      "\n",
+      "#Variable declaration\n",
+      "t = symbols('t')           #symbol defined\n",
+      "et1 = complex(50,86.6)     #defining complex number\n",
+      "\n",
+      "#calculations\n",
+      "et = (et1.real*sympy.sqrt(2)*sympy.cos(314*t))+et1.imag*sympy.sqrt(2)*sympy.cos(314*t+90)  #expression\n",
+      "\n",
+      "#Result\n",
+      "print et"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "50.0*sqrt(2)*cos(314*t) + 86.6*sqrt(2)*cos(314*t + 90)\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 10.9,Page number 506"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import cmath\n",
+      "import math\n",
+      "from sympy import *\n",
+      "import sympy\n",
+      "\n",
+      "#Variable declarations\n",
+      "V1, V2=symbols('V1 V2')\n",
+      "\n",
+      "#Calculations\n",
+      "V = 0.3*V1                                               #voltage(V)\n",
+      "I1 = 0.007*V1                                           #current \n",
+      "y11 = I1/V1                                             #y parameter\n",
+      "\n",
+      "I2 = -V/40                                               #current     \n",
+      "y21 = I2/V1                                              #y parameter\n",
+      "\n",
+      "I2 = V2/(((40+100)*200.)/((40+100)+200.))                #y parameter\n",
+      "y22 = I2/V2          #incorrect answer in textbook       #y parameter\n",
+      "\n",
+      "I1 = (-I2*200)/300                                       #current    \n",
+      "y12 = I1/V2         #incorrect answer in textbook        #y parameter\n",
+      "\n",
+      "#Results\n",
+      "print \"y11+y12 is\",round(y11+y12,5),\"mho\"\n",
+      "print \"y22+y12 is\",round(y22+y12,5),\"mho\"\n",
+      "print \"y21-y12 is\",round(y21-y12,5),\"mho\"\n",
+      "print \"\\n(The difference in answers is due to the y12 and y21 values calculated wrongly in the textbook)\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "y11+y12 is -0.0011 mho\n",
+        "y22+y12 is 0.00405 mho\n",
+        "y21-y12 is 0.0006 mho\n",
+        "\n",
+        "(The difference in answers is due to the y12 and y21 values calculated wrongly in the textbook)\n"
+       ]
+      }
+     ],
+     "prompt_number": 7
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 10.10,Page number 508"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "\n",
+      "#port 2 open circuited,port 1 excited\n",
+      "z11=1075+1075j                   #as z11=V1/I1=(1.52<45)/(10**-3<0)=1075+1075j\n",
+      "z21=2022-1075j                   #as z21=V2/I1=(2.29<-28)/(10**-3<0)=2022+1075j\n",
+      "\n",
+      "#port 1 open circuited and port 2 excited\n",
+      "z12=-1075j                       #as z12=V1/I2=(1.075<-90)/(10**3<0)=-1075j\n",
+      "z22=751-1073j                    #as z22=V2/I2=(1.31<-55)/(10**-3<0)=751-j1073\n",
+      "\n",
+      "#Calculations\n",
+      "z=z11-z12                        #parameters with reference to circuit\n",
+      "z1=z22-z12\n",
+      "z2=z21-z12\n",
+      "\n",
+      "#Results\n",
+      "print\"z11-z12(z) is\",z\n",
+      "print\"z22-z12(z1) is\",z1\n",
+      "print\"z21-z12(z2) is\",z2"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "z11-z12(z) is (1075+2150j)\n",
+        "z22-z12(z1) is (751+2j)\n",
+        "z21-z12(z2) is (2022+0j)\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 10.11,Page number 510"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "V2=6/7.                   #voltage source(V)\n",
+      "\n",
+      "#Calculations                  \n",
+      "Rth=V2                     #thevinin resistance(ohms)\n",
+      "Zl=Rth                     #load resistance(ohms)\n",
+      "\n",
+      "#Result\n",
+      "print\"load resistance is\",round(Zl,3),\"ohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "load resistance is 0.857 ohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 21
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Electronics_Devices_And_Circuits/chapter11.ipynb b/Electronics_Devices_And_Circuits/chapter11.ipynb
new file mode 100755
index 00000000..4150f842
--- /dev/null
+++ b/Electronics_Devices_And_Circuits/chapter11.ipynb
@@ -0,0 +1,170 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:9ece3b9f8730ff4f15d623a124d9415b373cdc935ed6cb089360bef5516a2604"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "                                Chapter 11: Cathode Ray Oscilloscope"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 11.2,Page number 532"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "E=120                  #electric field(V/m)              \n",
+      "B=5*10**-5             #magnetic field(T) \n",
+      "q=1.6*10**-19          #charge on electron(C)\n",
+      "u=10**6                #velocity of electron(m/s)\n",
+      "m=9.1*10**-31          #mass of electron(Kg) \n",
+      "a=9.81                 #acceleration of gravitation(m/s^2)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "fe=q*E                #force on electron due to electric field(N)\n",
+      "\n",
+      "#Part\n",
+      "fm=B*q*u             #force on electron due to magnetic field(N)\n",
+      "\n",
+      "#Part c\n",
+      "fg=m*a               #force on electron due to gravitational field(N)\n",
+      "\n",
+      "#Results\n",
+      "print\"force on electron due to electric field is\",fe,\"N\"\n",
+      "print\"force on electron due to magnetic field is\",fm,\"N\"\n",
+      "print\"force on electron due to gravitational field is\",fg,\"N\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "force on electron due to electric field is 1.92e-17 N\n",
+        "force on electron due to magnetic field is 8e-18 N\n",
+        "force on electron due to gravitational field is 8.9271e-30 N\n"
+       ]
+      }
+     ],
+     "prompt_number": 11
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 11.3,Page number 532"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "T1=1200.                         #temperature(k)\n",
+      "T2=1000.                         #temperature(k)\n",
+      "Ww=1.2*10**5                     #work function(eV)\n",
+      "k=8.62\n",
+      "Ie1=200                         #emission current density\n",
+      "T3=1500.                        #temperature(k)\n",
+      "\n",
+      "#Calculations\n",
+      "Ie2=Ie1*(T2/T1)**2*math.exp(-(Ww/k)*((1/T2)-(1/T1)))             #current density(mA/cm^2) at 1000k\n",
+      "Ie3=Ie1*(T3/T1)**2*math.exp(-(Ww/k)*((1/T3)-(1/T1)))             #current density(mA/cm^2) at 1000k\n",
+      "\n",
+      "#Results\n",
+      "print\"current density at 1000 k is\",round(Ie2,2),\"mA/cm^2\"\n",
+      "print\"current density at 1500 k is\",round(Ie3,2),\"mA/cm^2\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "current density at 1000 k is 13.65 mA/cm^2\n",
+        "current density at 1500 k is 3180.49 mA/cm^2\n"
+       ]
+      }
+     ],
+     "prompt_number": 7
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 11.4,Page number 533"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Ls=40                     #distance from screen(m)\n",
+      "d=1.5                     #distance between plates(cm)\n",
+      "Va=1200                   #accelerating potential(V) \n",
+      "L=3                       #length of CRT(m)\n",
+      "e=1.6*10**-19             #charge on electron(C)\n",
+      "m=9.1*10**-31             #mass of electron(Kg) \n",
+      "Y=4*10**-2                #vertical deflection(V)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "U=math.sqrt((2*e*Va)/m)   #velocity of electron upon striking screen(m/s)\n",
+      "\n",
+      "#Part\n",
+      "Vd=(2*d*Va*Y)/(L*Ls)      #deflecting voltage(V)\n",
+      "\n",
+      "#Part c\n",
+      "Vdmax=(m*d**2*U**2)/(e*L**2)   #maximum allowable deflection(V)\n",
+      "\n",
+      "#Results\n",
+      "print\"velocity of electron upon stricking the screen is\",round((U/1E+7),3),\"*10^7 m/s\"\n",
+      "print\"deflecting voltage is\",round(Vd/1E-2),\"V\"\n",
+      "print\"maximum allowable deflection is\",Vdmax,\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "velocity of electron upon stricking the screen is 2.054 *10^7 m/s\n",
+        "deflecting voltage is 120.0 V\n",
+        "maximum allowable deflection is 600.0 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Electronics_Devices_And_Circuits/chapter3.ipynb b/Electronics_Devices_And_Circuits/chapter3.ipynb
new file mode 100755
index 00000000..b37b068d
--- /dev/null
+++ b/Electronics_Devices_And_Circuits/chapter3.ipynb
@@ -0,0 +1,1540 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:cb1edbf7476adce6aba9bf1488bee35026e4b80ac8b3b01d96344eaf38909822"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "\n",
+      "Chapter 3:           SMALL SIGNAL MODELS,AMPLIFICATION AND BIASING"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.1,Page number 136"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "beeta=100            #current gain\n",
+      "Ic=2.5               #collector current(mA)\n",
+      "Io=-0.5              #output current(mA) \n",
+      "Rl=2.5               #load resistance(kohm)\n",
+      "\n",
+      "#Calculations\n",
+      "rpi=beeta*(25/Ic)   #dynamic resistance(ohms)\n",
+      "Ib=Io/(-beeta)      #as Io=-beeta*Ib\n",
+      "Vs=rpi*Ib           #signal voltage(V)\n",
+      "Vo=Rl*Io            #output voltage(V)\n",
+      "Av=Vo/Vs            #voltage gain\n",
+      "Ai=Io/Ib            #current gain\n",
+      "\n",
+      "#Results\n",
+      "print\"signal voltage is\",Vs,\"mV\"\n",
+      "print\"current gain is\",Ai\n",
+      "print\"voltage gain is\",round(Av/1E-3)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "signal voltage is 5.0 mV\n",
+        "current gain is -100.0\n",
+        "voltage gain is -250.0\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.2,Page number 139"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Id=1.6               #drain current(mA)\n",
+      "Vgs=-3               #gate to source voltage(V)\n",
+      "Id1=.4               #drain current(mA)\n",
+      "Vgs1=-4              #gate to source voltage(V)   \n",
+      "Vp=-5                #peak voltage(V) by solving equations 1.6=Idss(1+3/Vp)^2 and .4=Idss(1+4/Vp)^2\n",
+      "Idss=10              #small signal drain current(mA) by solving equations 1.6=Idss(1+3/Vp)^2 and .4=Idss(1+4/Vp)^2\n",
+      "                      \n",
+      "#Calculations\n",
+      "gmo=-(2*Idss)/Vp                #transconductance(mS)\n",
+      "gm=gmo*(math.sqrt(Id/Idss))     #transconductance(uS)\n",
+      "gm1=gmo*(math.sqrt(Id1/Idss))   #transconductance(uS) \n",
+      "\n",
+      "#Results\n",
+      "print\"Idss and Vp are\",Idss,\"mA and\",Vp,\"V\"\n",
+      "print\"gmo is\",gmo,\"mS\"\n",
+      "print\"gm at Id is\",round(gm/1E-3),\"and gm at Id1 is\",round(gm1/1E-3),\"uS\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Idss and Vp are 10 mA and -5 V\n",
+        "gmo is 4 mS\n",
+        "gm at Id is 1600.0 and gm at Id1 is 800.0 uS\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.3,Page number 140"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "gm=1600             #gm(us)\n",
+      "rd=50               #resistance(kohms)\n",
+      "Rl=5                #load resistance(kohms)\n",
+      "\n",
+      "#Calculations\n",
+      "Av=-gm*Rl           #Vgs=Vs from circuit model\n",
+      "                    #Vo=-(gm*Vgs)*Rl\n",
+      "                    #as Av=Vo/Vs=-gm*Rl     \n",
+      "\n",
+      "#Result\n",
+      "print\"voltage gain of the circuit is\",round(Av/1E+3)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "voltage gain of the circuit is -8.0\n"
+       ]
+      }
+     ],
+     "prompt_number": 5
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.4,Page number 145"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "beta=100.       #current gain\n",
+      "rpi=2*10**3     #dynamic resistance(ohms)\n",
+      "rx=500          #resistance(ohms)\n",
+      "ro=250*10**3    #output resistance(ohms)\n",
+      "R1=50*10**3     #resistance(k ohms)   \n",
+      "R2=10*10**3     #resistance(k ohms)\n",
+      "Rc=5*10**3      #collector current(k ohms) \n",
+      "Rl=5*10**3.     #load current(k ohms)\n",
+      "Rs=1*10**3      #source resistance(k ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "Rb=(R1*R2)/(R1+R2)               #equivalent resistance of R1 and R2(kohms)\n",
+      "r=rpi+rx                         #series resistance of rpi and rx(k ohms) \n",
+      "gm=beta/rpi                      #transconductance(mS)\n",
+      "Vo=-gm*((Rc*Rl)/(Rc+Rl))*.526    #output voltage(V) as \n",
+      "Av=Vo                            #voltage gain\n",
+      "Ai=Av*((Rs+((Rb*r)/(Rb+r)))/Rl)  #current gain \n",
+      "\n",
+      "#Results\n",
+      "print\"source to load voltage gain is\",Av\n",
+      "print\"source to load current gain is\",Ai,\"(Solution given in the textbook is incorrect)\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "source to load voltage gain is -65.75\n",
+        "source to load current gain is -38.43745 (Solution given in the textbook is incorrect)\n"
+       ]
+      }
+     ],
+     "prompt_number": 8
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.5,Page number 148"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "beta=100.       #current gain\n",
+      "rd=50*10**3     #internal dynamic resistance(ohms\n",
+      "gm=5*10**-3     #transconductance(mS)\n",
+      "R1=50*10**3     #resistance(ohms)   \n",
+      "R2=10*10**3      #resistance(ohms)\n",
+      "Rs=10*10**3      #source current(ohms) \n",
+      "Rg=1*10**6.      #gate resistance(ohms)\n",
+      "Rd=10*10**3      #drain resistance(ohms)\n",
+      "\n",
+      "#Calculations                      \n",
+      "Vgs=(Rg/(Rs+Rg))                 #gate to source voltage (V) as Vgs=Vs((Rg/(Rs+Rg))   \n",
+      "Av=-Vgs*gm*((rd*Rd)/(rd+Rd))      #voltage gain,Av=Vo/Vs and Vo=-gmVgs(rd||Rd)\n",
+      "Ai=Av*((Rs+Rg)/Rd)               #current gain\n",
+      "\n",
+      "#Results\n",
+      "print\"source to load voltage gain is\",round(Av)\n",
+      "print\"source to load current gain is\",round(Ai)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "source to load voltage gain is -41.0\n",
+        "source to load current gain is -4167.0\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.6,Page number 149"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Rs=500           #collector current(k ohms) \n",
+      "Io=-1*10**-3     #output current(mA) \n",
+      "Rc=5*10**3.       #collector resistance(ohms)\n",
+      "hie=2*10**3\n",
+      "hoe=10*10**-6.    \n",
+      "hfe=100.\n",
+      "hre=5*10**-4\n",
+      "Rb=50*10**3.     #base resistance(ohms)\n",
+      "\n",
+      "#Calculations                      \n",
+      "Io1=-1/(1+Rc*hoe)*hfe   #as Io=-1/(1+Rc*hoe)*hfe*Ib \n",
+      "Ib=-1/Io1               #base current(uA)\n",
+      "Vo=Io*Rc                #output voltage(V)\n",
+      "Vi=hie*Ib+Vo*hre        #input voltage(V)\n",
+      "Is=Ib+Vi/Rb             #source current(ohms)\n",
+      "Ai=Io/Is                #current gain\n",
+      "Vs=(Is*Rs)+Vi           #source voltage(V)\n",
+      "Av=Vo/Vs                #voltage gain\n",
+      "\n",
+      "#Results\n",
+      "print\"source to load voltage gain is\",round(Av/1E-3)\n",
+      "print\"source to load current gain is\",round(Ai/1E-3)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "source to load voltage gain is -189.0\n",
+        "source to load current gain is -92.0\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.7,Page number 153"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "beeta=100.      #current gain  \n",
+      "Ic=4.           #collector current(mA)\n",
+      "Vbe=0.7         #base to emitter voltage(V)  \n",
+      "Re=2.           #emitter resistance(ohms)\n",
+      "Vcc=32.         #supply voltage(V)\n",
+      "abeeta=40.      #actual current gain\n",
+      "\n",
+      "#Calculations\n",
+      "Ib=Ic/beeta                        #base current(mA)\n",
+      "Rb=(Vcc-Vbe-((Ib+Ic)*Re))/Ib       #as Vcc=(Ib*Rb)+Vbe+(Ib+Ic)*Re              \n",
+      "Ib=(Vcc-Vbe-8)/(Rb+Re)             #as Vcc=Rb*Ib+Vbe+(Ib+Ic)*Re\n",
+      "Ic1=abeeta*Ib                      #collector current(mA)\n",
+      "deltaIc=Ic-Ic1                     #change in collector current(mA)\n",
+      "\n",
+      "#Result\n",
+      "print\"change in Ic when beeta=40 is\",deltaIc,\"mA\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "change in Ic when beeta=40 is 2.4 mA\n"
+       ]
+      }
+     ],
+     "prompt_number": 11
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.8,Page number 155"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Rb1=36                   #base resistance 1(kohms)\n",
+      "Rb2=12                   #base resistance 2(kohms)\n",
+      "Rc=4                     #emitter resistancce(kohms) \n",
+      "Re=1.8                   #emitter resistance(kohms)    \n",
+      "Vcc=12                   #supply voltage(V)\n",
+      "Vbe=0.7                  #base to emitter voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "Rb=(Rb1*Rb2)/(Rb1+Rb2)   #base resistance(ohms)\n",
+      "Vbb=Vcc*(Rb2/(Rb1+Rb2))  #voltage supply to base(V)\n",
+      "                         #(10.8*Ib)+(1.8*Ic)=2.3    equation 1...solving -Vbb+RbIb+Vbe+(Ib+IC)Re\n",
+      "                          #(1.8*Ib)+(5.8*Ic)+Vce=12  equation 2  solving -Vcc+RcIc+Vce+(Ob+Ic)Re\n",
+      "#Part a\n",
+      "beeta=50              #current gain  \n",
+      "Ib=2.3/100.8          #(10.8*Ib)+(90*Ib)=2.3 ,using -Vbb+Rb*Ib+Vbe+(Ib+Ic)*Re  \n",
+      "                      #as Ic=50Ib and putting this in equation 1      \n",
+      "Icq=Ib*beeta\n",
+      "Vceq=Vcc-(1.8*Ib)-(5.8*Icq) #from equation 2\n",
+      "\n",
+      "#Part b\n",
+      "beeta=150           #current gain  \n",
+      "Ib=2.3/280.8        # (10.8*Ib)+(270*Ib)=2.3,using -Vcc+Rc*Ic+Vce+(Ib+Ic)*Re   \n",
+      "                    #as Ic=150Ib and putting this in equation 1      \n",
+      "Icq1=Ib*beeta                           \n",
+      "Vceq1=Vcc-(1.8*Ib)-(5.8*Icq1)         #from equation 2\n",
+      "\n",
+      "#Results\n",
+      "print\"when beeta increases by 300%,Icq increases by\",round((((Icq1-Icq)/Icq1)*100),1),\"%\"\n",
+      "print\"when beeta increases by 300%, Vceq increases by\",round(((Vceq-Vceq1)/Vceq)*100),\"%\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "when beeta increases by 300%,Icq increases by 7.1 %\n",
+        "when beeta increases by 300%, Vceq increases by 9.0 %\n"
+       ]
+      }
+     ],
+     "prompt_number": 24
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.9,Page number 156"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Ic=4                      #collector current(mA)\n",
+      "Vce=8                     #collector emitter voltage(V) \n",
+      "beeta=100                 #current gain   \n",
+      "Rb2=24                    #base resistance(kohms)\n",
+      "Vbe=0.7                   #base to emitter voltage(V)\n",
+      "Rc=4                     #collector current(kohm)\n",
+      "Re=2                     #emitter resistance(kohms) \n",
+      "Ib=0.04                  #base current(mA) \n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Vcc=(Ic*Rc)+Vce+Ic*Re         #from formula Vcc=IcRc+Vce+(Ic+Ib)Re..eq 1\n",
+      "\n",
+      "#Part b\n",
+      "Rb1=Rb2*(Vcc-(Vbe+Ic*Re))/((Vbe+Ic*Re)+Ib)  #from eq 1 and also from Vbb= Vcc(Rb2/(Rb1+Rb2))\n",
+      "Rb=(Rb1*Rb2)/(Rb1+Rb2)                      #base resistance(ohms)\n",
+      "Vbb=(Vcc*Rb2)/(Rb1+Rb2)                     #supply to base(V)\n",
+      "\n",
+      "#Part c\n",
+      "abeeta=40                                 #actual current gain\n",
+      "Ib1=((Vbe+Re*Ic)-Vbe)/((1+abeeta)*2+Rb)   #from equation Vbb=IbRb+Vbe+(Ic+Ib)Re\n",
+      "Ic1=abeeta*Ib1                            #collector gain\n",
+      "\n",
+      "#Results\n",
+      "print\"a)Vcc is\",Vcc,\"V\"\n",
+      "print\"b)values are Rb1:\",round(Rb1,2),\"KOhms,Rb:\",round(Rb,2),\"kohm and Vbb:\",round(Vbb,2),\"V\" \n",
+      "print\"c)actual value of Ic1\",round(Ic1,2),\"mA\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)Vcc is 32 V\n",
+        "b)values are Rb1: 63.98 KOhms,Rb: 17.45 kohm and Vbb: 8.73 V\n",
+        "c)actual value of Ic1 3.22 mA\n"
+       ]
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.10,Page number 158"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vcc=10       #supply voltage(V)\n",
+      "Rc=4.7       #collector current(kohms)\n",
+      "Rb=250       #base resistance(kohms)\n",
+      "Re=1.2       #emitter resistance(kohms)\n",
+      "beeta=100    #current gain\n",
+      "Vbe=0.7      #base to emitter voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Ib=(Vcc-Vbe)/(Rb+(beeta*(Rc+Re)))   #base current(uA)\n",
+      "Ic=beeta*Ib                         #collector current(mA)\n",
+      "Vce=Vcc-Ic*(Rc+Re)                  #collector to emitter voltage(V)\n",
+      "#Part b\n",
+      "beeta1=150                          #current gain\n",
+      "Ib1=(Vcc-Vbe)/(Rb+(beeta1*(Rc+Re))) #base current(mA)\n",
+      "Ic1=beeta1*Ib1                      #collector current(mA)\n",
+      "Vce1=Vcc-Ic1*(Rc+Re)                #collector to emitter voltage(V)\n",
+      "deltaIc=((Ic1-Ic)/Ic)*100           #small change in Ic(mA)\n",
+      "deltaVce=((Vce-Vce1)/Vce)*100       #small change in Vce(V)\n",
+      "\n",
+      "#Results\n",
+      "print\"values of Ic is\",round(Ic,2),\"mA and Vce:\",round(Vce,2),\"V\"\n",
+      "print\"values of Ic1 is\",round(Ic1,2),\"mA and Vce1 is\",round(Vce1,2),\"V\"\n",
+      "print\"% change in Ic is\",round(deltaIc,2),\"% and in Vce is\",round(deltaVce,2),\"%\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "values of Ic is 1.11 mA and Vce: 3.47 V\n",
+        "values of Ic1 is 1.23 mA and Vce1 is 2.75 V\n",
+        "% change in Ic is 11.01 % and in Vce is 20.74 %\n"
+       ]
+      }
+     ],
+     "prompt_number": 12
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.11,Page number 160"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Id=3              #drain current(mA)\n",
+      "Vds=12            #drain source voltage(V)\n",
+      "Vgs=-3            #gate source voltage(V)\n",
+      "Vdd=36            #drain voltage(V)\n",
+      "Vgg=12            #gate voltage(V)\n",
+      "Rg=12             #gate resistance(Mohms)\n",
+      "\n",
+      "#Calculations\n",
+      "R1=(Rg*Vdd)/Vgg             #resistance(Mohms)\n",
+      "R2=(Rg*R1)/(R1-Rg)          #resistance(kohms)\n",
+      "Rs=(Vgg-Vgs)/Id             #resistance(kohms)\n",
+      "Rd=(Vdd-Vds-Id*Rs)/Id       #as Vdd-IdRd-Vds-IdRs\n",
+      "Vgs=-3.6                    #consider Vgs increases by 20%\n",
+      "Idnew=(Vgg-Vgs)/Rs          #new drain current(mA)\n",
+      "\n",
+      "#Results\n",
+      "print\"value of R1:\",R1,\"MOhm,R2:\",R2,\"Mohms,Rs:\",Rs,\"KOhm and Rd:\",Rd,\"kohms\"\n",
+      "print\"new Id is\",Idnew,\"mA\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "value of R1: 36 MOhm,R2: 18 Mohms,Rs: 5 KOhm and Rd: 3 kohms\n",
+        "new Id is 3.12 mA\n"
+       ]
+      }
+     ],
+     "prompt_number": 13
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.12,Page number 161"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "from sympy import*\n",
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "k=0.0002                    #device parameter\n",
+      "Vt=4                        #thevinin voltage(V)   \n",
+      "Vdd=24                      #drain voltage(V)\n",
+      "Id0=3                        #drain current(mA)  \n",
+      "\n",
+      "#Calculations\n",
+      "Vgs=(math.sqrt(Id0/k))+4   #as Id=k(Vgs-Vt)^2\n",
+      "Rd=-(Vgs-Vdd)/Id0         #as Vds=Vdd-IdRd and Vgs=Vds=7.87                        \n",
+      "k=0.0003                  #device parameter \n",
+      "\n",
+      "Id=symbols('Id')\n",
+      "expr=solve(Id**2-7.5*Id+13.7,Id)\n",
+      "print\"equation has 2 solutions\",expr                                    # putting value of k=0.0003 in eq of Id,\n",
+      "Id1=3.15                                    # we get Vgs=Vds=24-5.4Id and putting Vgs again in Id we get,\n",
+      "                                    # Id^2-7.5Id+13.7=0\n",
+      "                                    \n",
+      "Idchange=((Id1-Id0)/Id0)*100                                                    #changed Id(mA)\n",
+      "\n",
+      "#Result\n",
+      "print\"change in Id is\",Idchange,\"% increase\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "equation has 2 solutions [3.14792027106039, 4.35207972893962]\n",
+        "change in Id is 5.0 % increase\n"
+       ]
+      }
+     ],
+     "prompt_number": 18
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.13,Page number 162"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration \n",
+      "Vt=2                        #threshold voltage(V)\n",
+      "Id=8                        #drain current(mA)\n",
+      "Vgs=6.                       #gate to source voltage(V)\n",
+      "k=0.5                       #device parameter\n",
+      "Vdd=24                      #drain voltage(V)\n",
+      "Vds=10                       #drain to source voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Vgs1=4                                            #gate to source voltage(V) \n",
+      "Id1=k*(Vgs1-Vt)**2                                 #drain current(mA)\n",
+      "\n",
+      "#Part b\n",
+      "Vgg=3*Vgs1                                         #gate voltage(V)\n",
+      "R2=(Vdd/Vgg)-1                                    #resistance(Mohms)\n",
+      "Rs=(Vgg-Vgs1)/2                                    #source resistance(k ohms)\n",
+      "Rd=(Vdd-Vds-Id1*Rs)/2\n",
+      "\n",
+      "#part c\n",
+      "K=1.5*k                   #increased by 50%\n",
+      "Vgs2=3.67                 #solving 12=Vgs+4Id and Id=0.75(Vgs-2)^2 \n",
+      "Id2=2.08                   #drain current when k is increased(mA)\n",
+      "Vds1=Vdd-Id2*(Rd+Rs)      #drain to source voltage(V)\n",
+      "\n",
+      "#Results\n",
+      "print\"drain current defined by Vgs=4 and Vds=10 is\",Id1,\"mA\"\n",
+      "print\"value of Rs,Rd,R2 are\",Rs,\"k ohms,\", Rd,\"k ohms,\",R2,\"Mohms resp.\"\n",
+      "print\"actual value of Id and Vds are\",Id2,\"mA,\",Vds1,\"mA and\",Vds,\" V resp.\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "drain current defined by Vgs=4 and Vds=10 is 2.0 mA\n",
+        "value of Rs,Rd,R2 are 4 k ohms, 3.0 k ohms, 1 Mohms resp.\n",
+        "actual value of Id and Vds are 2.08 mA, 9.44 mA and 10  V resp.\n"
+       ]
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.14,Page number 166"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Ic=10                       #collector current(mA)\n",
+      "beeta=100                   #current gain\n",
+      "Vbe=0.7                     #base to emitter voltage(V)\n",
+      "Vcc=10                      #supply voltage(V) \n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "R=(beeta*(Vcc-Vbe))/((beeta+2)*Ic)               #resistance(k ohms)  \n",
+      "beeta1=200                                       #current gain\n",
+      "Ic1=(beeta1/(beeta1+2))*((Vcc-Vbe)/R)            #collector current(mA)\n",
+      "Icchange=((Ic-Ic1)/Ic)                           #change in collector current(mA)  \n",
+      "\n",
+      "#Part b\n",
+      "Ic2=0.1                                          #collector current(mA)\n",
+      "R1=(beeta*(Vcc-Vbe))/((beeta+2)*Ic)              #resistance(k ohms)\n",
+      "Ic3=(beeta1/(beeta1+2))*((Vcc-Vbe)/R1)           #collector current(mA)\n",
+      "Icchange1=((Ic2-Ic3)/Ic2)                        #change in collector current(mA)\n",
+      "\n",
+      "#Results\n",
+      "print\"% change in Ic is\",round(Icchange,1),\"% increase\"\n",
+      "print\"% change in Ic is\",round(Icchange1,1),\"% increase\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "% change in Ic is 1.0 % increase\n",
+        "% change in Ic is 1.0 % increase\n"
+       ]
+      }
+     ],
+     "prompt_number": 30
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.15,Page number 167"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vcc=6                      #supply voltage(V)\n",
+      "R=1.2                      #resistance(k ohms)\n",
+      "Vbe=0.7                    #base to emitter voltage(V) \n",
+      "beeta=100.                 #current gain\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Ir=(Vcc-Vbe)/R             #current(mA)\n",
+      "I=(beeta/(beeta+3))*Ir     #current(mA)as transistors are identiical,I=Ie\n",
+      "\n",
+      "#Result\n",
+      "print\"load current I is\",round(I,2),\"mA\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "load current I is 4.29 mA\n"
+       ]
+      }
+     ],
+     "prompt_number": 34
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.16,Page number 171"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math \n",
+      "\n",
+      "#Variable declaration\n",
+      "Idss=10              #drain current for zero bias(mA)\n",
+      "Vp=-4                #peak voltage(V)\n",
+      "Idq=Id=2.5           #quienscent drain current(mA)\n",
+      "Vdd=24               #voltage drain drain(V)\n",
+      "Vgg=4                #gate voltage(V)\n",
+      "R1=22                #resistance(Mohms)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Vgs=Vp*(1-(math.sqrt(Id/Idss)))         #solving Id=Idss(1-Vgs/Vp)^2\n",
+      "Rs=(Vgg-Vgs)/Id                         #as Vgg-Vgs-IdRs=0 ,Id=Is \n",
+      "Rd=2.5*Rs                               #given\n",
+      "R2=(Vgg*R1)/(R1-Vgg)                    #from Vgg=(R1*R2)/(R1+R2)\n",
+      "\n",
+      "#Part b\n",
+      "gmo=-(2*Idss)/Vp                       #transconductance(mS)\n",
+      "gm=gmo*(math.sqrt(Id/Idss))            #transconductance(mS)\n",
+      "\n",
+      "#Part c\n",
+      "Av=-gm*Rd                              #voltage gain\n",
+      "\n",
+      "#Results\n",
+      "print\"values of Rs:\",Rs,\"Kohms,Rd:\",Rd,\"k ohms and R2 is\",round(R2,1),\"M ohms\"\n",
+      "print\"value of gm is\",gm,\"mS and gmo is\",gmo,\"mS\"\n",
+      "print\"voltage amplification is\",Av"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "values of Rs: 2.4 Kohms,Rd: 6.0 k ohms and R2 is 4.0 M ohms\n",
+        "value of gm is 2.5 mS and gmo is 5 mS\n",
+        "voltage amplification is -15.0\n"
+       ]
+      }
+     ],
+     "prompt_number": 15
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.17,Page number 174"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "beeta=98.                          #current gain\n",
+      "rpi=1.275                          #dynamic resistance(k ohms)\n",
+      "Rb=220.                            #base resistance(k ohms)\n",
+      "Re=3.3                             #emitter resistance(k ohms)\n",
+      "Vcc=12.                            #supply voltage(V)\n",
+      "Vbe=0.7                            #base to emitter voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "x=rpi/(1+beeta)\n",
+      "Av=Re/(Re+x)                     #voltage gain\n",
+      "\n",
+      "#Part b\n",
+      "Zb=rpi+(1+beeta)*Re            #impedance(k ohms)\n",
+      "Zi=(Zb*Rb)/(Zb+Rb)             #input impedance(k ohms)\n",
+      "Zo=(Re*x)/(Re+x)               #output impedance(k ohms)\n",
+      "\n",
+      "#Part c\n",
+      "Ib=(Vcc-Vbe)/(Rb+(Re*(1+beeta)))     #as Ie=(1+beeta)*Ib\n",
+      "Ic=beeta*Ib                         #collector current(mA)\n",
+      "rpi=beeta*(25/Ic)                   #dynamic resistance(k ohms)\n",
+      "\n",
+      "#Results\n",
+      "print\"voltage gain is\",round(Av,3)\n",
+      "print\"input impedance is\",round(Zi,1),\"KOhm and output impedance is\",round((Zo/1E-3),1),\"ohms\"\n",
+      "print\"value of Ic is\",round(Ic,3),\"mA\"\n",
+      "print\"value of rpi is\",round((rpi/1E+3),3),\"k ohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "voltage gain is 0.996\n",
+        "input impedance is 131.7 KOhm and output impedance is 12.8 ohms\n",
+        "value of Ic is 2.026 mA\n",
+        "value of rpi is 1.21 k ohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.18,Page number 176"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "from sympy import*\n",
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Idss=16                           #drain current bias to zero(mA) \n",
+      "Vp=-4                             #pinch off voltage(V)  \n",
+      "Rg=1                              #gate resistance(ohms)\n",
+      "Rs=2.2                            #sourse resistance(ohm)\n",
+      "Vdd=9                             #drain drain voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "#Id=Idss*(1-(Vgs/Vp))**2\n",
+      "# putting value of Vgs=2.2*Id inequation of Id,we get\n",
+      "#Id**2-3.84Id+3.31   \n",
+      "\n",
+      "Id=symbols('Id')\n",
+      "expr=solve(Id**2-3.84*Id+3.31,Id)\n",
+      "print expr\n",
+      "Id1=1.3    \n",
+      "Vgs=-Id1*Rs                                         #gate to source voltage(V)\n",
+      "gm0=-(2*Idss)/Vp                                    #transconductance(mS)\n",
+      "gm=gm0*(1-(Vgs/Vp))                                 #transconductance(mS)  \n",
+      "rm=1/gm                                             #transresistance(k ohms) \n",
+      "Av=(Rs*gm)/(1+(Rs*gm))                              #voltage gain\n",
+      "\n",
+      "#Part b\n",
+      "Zi=Rg                                               #input impedance(Mohms)\n",
+      "Zo=(Rs*rm)/(Rs+rm)                                  #output impedance(ohms)\n",
+      "\n",
+      "#Results\n",
+      "print\"voltage gain is\",round(Av,3)\n",
+      "print\"input and output impedences are\",Zi,\"Mohms and\",round((Zo/1E-3),1),\"ohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        " [1.30648553399288, 2.53351446600712]\n",
+        "voltage gain is 0.834\n",
+        "input and output impedences are 1 Mohms and 365.7 ohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.19,Page number 182"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Re=0.56                          #emitter resistance(k ohms)\n",
+      "beta=1600                        #current gain\n",
+      "R1=110                           #resistance(k ohms)\n",
+      "R2=330                           #resistance(k ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Av1=Re*(beta+1)               #voltage gain\n",
+      "\n",
+      "#part b\n",
+      "Rb=(R1*R2)/(R1+R2)             #base resistance(k ohms)\n",
+      "Vs=(1.56/(Re*(beta+1)))+1       #source voltage(V) \n",
+      "Avs=1/Vs\n",
+      "\n",
+      "#part c\n",
+      "R=1+(1+beta)*Re                                    #resistance presented to Ib\n",
+      "I=Rb/(Rb+R)                                        #I=Ib/Ii \n",
+      "Ai=(1+beta)*I                                      #current gain\n",
+      "\n",
+      "#part d\n",
+      "Rl=10*10**3                             #load resistance(ohm)\n",
+      "Re1=(Re*Rl)/(Re+Rl)                     #emitter resistance(k ohms)\n",
+      "R1=1+(1+beta)*Re1                       #resistance presented to Ib(k ohms)\n",
+      "I1=Rb/(Rb+R1)                           #I1=Ib/Ii\n",
+      "Ai1=(beta+1)*I1                         #current gain\n",
+      "Av2=Re1*(1+beta)                        #voltage gain\n",
+      "\n",
+      "#Results\n",
+      "print\"a)voltage gain is\",Av1\n",
+      "print\"b)Avs is\",round(Avs,2)\n",
+      "print\"c)Ai is\",round(Ai,2)\n",
+      "print\"when output Vo1 feeds a load of 10 k ohms Ai is\",round(Ai1),\"and Av2 is\",round(Av2)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)voltage gain is 896.56\n",
+        "b)Avs is 1.0\n",
+        "c)Ai is 134.02\n",
+        "when output Vo1 feeds a load of 10 k ohms Ai is 134.0 and Av2 is 897.0\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.20,Page number 184"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "beeta1=120.                       #current gain\n",
+      "beeta2=160.                      #current gain\n",
+      "Vcc=18                           #supply voltage(V)\n",
+      "Rc=0.1                           #collector resistance(ohms)\n",
+      "Rb=2*10**3.                       #base resistance(ohms)\n",
+      "Vbe=0.7                          #base to emitter voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "Ib1=(Vcc-Vbe)/(Rb+(beeta1*beeta2*Rc))#base current(uA)\n",
+      "Ib2=beeta1*Ib1                      #base current(mA)\n",
+      "Ie1=(beeta1+1)*Ib1                  #emitter current(mA)\n",
+      "Ic=Ie1+(beeta2*Ib2)                 #collector current(mA)\n",
+      "Vo=Vcc-(Ic*Rc)                      #output voltage(V)\n",
+      "Vi=Vo-Vbe                           #input voltage(V)\n",
+      "\n",
+      "#Results\n",
+      "print\"dc biased current is\",round(Ic,1),\"mA\"\n",
+      "print\"output voltage\",round(Vo,2),\"V\"\n",
+      "print\"input voltage\",round(Vi,2),\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "dc biased current is 85.3 mA\n",
+        "output voltage 9.47 V\n",
+        "input voltage 8.77 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 13
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.21,Page number 191"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "deltaId=2.                         #change in Id(mA)\n",
+      "deltaVgs=1.                        #change in Vgs(V)\n",
+      "deltaVds=5.                        #change in Vds(V)\n",
+      "Idss=10.                           #drain current biased to zero(mA)\n",
+      "Id=5.                              #drain current(mA)\n",
+      "Vp=-6.                             #pinch off voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "gm=(deltaId)/(deltaVgs)            #transconductance(mS)\n",
+      "rds=(deltaVds)/(deltaId)           #resistance(k ohms)\n",
+      "gm0=-(2*Idss)/Vp                   #transconductance(mS)\n",
+      "gm=gm0*(math.sqrt(Id/Idss))        #transconductance(mS)\n",
+      "\n",
+      "#Part b\n",
+      "R1=4.5                             #resistance(k ohms)\n",
+      "R2=2                               #resistance(k ohms)\n",
+      "Av=gm*((R1*R2)/(R1+R2))            #voltage gain\n",
+      "\n",
+      "#Results\n",
+      "print\"drain current biased to zero is\",Idss,\"mA and pinch off voltage is\",Vp,\"V\"\n",
+      "print\"value of gm and rds are\",round(gm,2),\"mS and\",rds,\"k ohms\"\n",
+      "print\"small signal amplifier gain is\",round(Av,2)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "drain current biased to zero is 10.0 mA and pinch off voltage is -6.0 V\n",
+        "value of gm and rds are 2.36 mS and 2.5 k ohms\n",
+        "small signal amplifier gain is 3.26\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.22,Page number 193"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Idson=0.2\n",
+      "Vgs=5                      #gate to source voltage(V)\n",
+      "Vdd=12                     #drain voltage(V)\n",
+      "Vt=2                       #thevinine voltage(V)\n",
+      "R1=100.                    #resistance(k ohms)                               \n",
+      "R2=100.                    #resistance(k ohms)   \n",
+      "Rd=30                      #drain resistance(K ohms)\n",
+      "Rs=6                       #source resistance(k ohms)\n",
+      "deltaVdd=0.3               #change in Vdd(V)\n",
+      "rds=50                     #internal drain to source resistance()\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "k=Idson/((Vgs-Vt)**2)              #device parameter\n",
+      "Vgg=Vdd*(R1/(R1+R2))               #gate voltage(V)\n",
+      "Vgs=4.89                           #gate to source voltage(V)\n",
+      "Id=k*(Vgs-Vt)**2                   #drain current(mA)\n",
+      "Vds=Vdd-((Rd+Rs)*Id)               #drain to source voltage(V)\n",
+      "gm=2*(math.sqrt(k*Id))             #transconductance(mS)\n",
+      "deltaVgg=deltaVdd*(R2/(R1+R2))     #change in Vgg(V)\n",
+      "\n",
+      "vgs=0.105                          #as vgs=0.15-6id where id=u*vgs/(rds+Rs+Rd)=0.74vgs after solving\n",
+      "id= 0.074*vgs*10**3\n",
+      "\n",
+      "#Results\n",
+      "print\"id is\",id,\"uA\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "id is 7.77 uA\n"
+       ]
+      }
+     ],
+     "prompt_number": 5
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.23,Page number 194"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "deltaId=1                         #change in Id(mA)\n",
+      "deltaVgs=0.75                     #change in Vgs(V) \n",
+      "rd=100                            #internal drain resistance(k ohms)\n",
+      "Rd=100                            #drain resistance(k ohms)\n",
+      "Vgs=2                             #as Vgs= 2sinwt                \n",
+      "\n",
+      "#Calculations\n",
+      "gm=(deltaId)/(deltaVgs)           #transconductance(m)  \n",
+      "Vo=-gm*Vgs*((rd*Rd)/(rd+Rd))      # as Vi=2sin(w*t)\n",
+      "\n",
+      "#Results\n",
+      "print\"value of Vo is\",round(Vo),\"*sinwt mV\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "value of Vo is -133.0 *sinwt mV\n"
+       ]
+      }
+     ],
+     "prompt_number": 50
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.24,Page number 195"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Finding resistance\n",
+      "\n",
+      "#Variable declaration\n",
+      "Rd=4                 #drain resistance(ohms)\n",
+      "Rs=2.5               #ource resistance(ohms)      \n",
+      "R1=200*10**3         #resistance(ohms)\n",
+      "R2=100*10**3         #resistance(ohms)\n",
+      "gm=2.5               #transconductance(mS)\n",
+      "rd=60                #internal drain resistance(ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part b\n",
+      "Ro=Rs/(1+(((1+gm*rd)*Rs)/(rd+Rd)))   #output resistance(ohms)\n",
+      "\n",
+      "#Part c\n",
+      "Rd1=0                              #drain resistance\n",
+      "Ro1=Rs/(1+(((1+gm*rd)*Rs)/rd))     #output resistance(ohms)\n",
+      "\n",
+      "#Results\n",
+      "print\"value of Ro is\",round(Ro/1E-3),\"ohms\"\n",
+      "print\"value of Ro1 is\",round(Ro1/1E-3),\"ohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "value of Ro is 362.0 ohms\n",
+        "value of Ro1 is 343.0 ohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 60
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.25,Page number 196"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "beeta=100                      #current gain factor\n",
+      "Vbe=0.7                        #base to emitter voltage(V)\n",
+      "Rb=250                         #base resistance(k ohms)\n",
+      "Vee=10                         #emitter voltage(V)\n",
+      "Re=1                           #emitter resistance(k ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "Ib=(Vee-Vbe)/(Rb+1+beeta)       # solving Rb*Ib+Vbe+(Ic+Ib)=Vee and putting Ic+Ib=(1+beeta)Ib\n",
+      "Ic=beeta*Ib                     #collector current(mA)\n",
+      "rpi=beeta*(25/Ic)               #dynamic resistance(ohms)    \n",
+      "Vi=(rpi*Ib)+(1+beeta)*Re*Ib     #input voltage(V)\n",
+      "Ri=Vi/Ib                        #input resistance(k ohms)\n",
+      "\n",
+      "#Results\n",
+      "print\"value of Ri is\",round((Ri/1E+1),1),\"K ohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "value of Ri is 104.5 K ohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 35
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.26,Page number 197"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "beeta=125                       #current gain\n",
+      "gm=35                           #transconductance(mS)\n",
+      "Re=4                            #emitter resistance(k ohms)\n",
+      "Rb=1.5                          #base resistance(k ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "rpi=beeta/gm                   #dynamic resistance(k ohms)\n",
+      "Ri=rpi+((1+beeta)*Re)          #input resistance(k ohms) \n",
+      "Ro=((Rb+rpi)*Re)/((Rb+rpi)+((1+beeta)*Re))  #output resistance(ohms) as Ro=Vo/Isc\n",
+      "\n",
+      "#Part b                                 \n",
+      "f=((1+beeta)*Re)/(Rb+rpi+((1+beeta)*Re))  #transfer function\n",
+      "\n",
+      "#Results\n",
+      "print\"value of Ri is\",Ri,\"K ohms and Ro is\",round(Ro,4),\"k\"\n",
+      "print\"transfer function is\",round(f,2)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "value of Ri is 507 K ohms and Ro is 0.0354 k\n",
+        "transfer function is 0.99\n"
+       ]
+      }
+     ],
+     "prompt_number": 6
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.28,Page number 199"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration \n",
+      "Vcc=16               #supply voltage(V)\n",
+      "Vc=12                 #collector voltage(V)\n",
+      "Ic=8                  #collector current(mA)\n",
+      "Ic1=12                \n",
+      "deltaIc=2000          #collector current(uA)\n",
+      "deltaVce=4            #collector emitter voltage(Vce) \n",
+      "deltaIb=20            #base current(mA)       \n",
+      "Rl=2.                 #load reistance(k ohms)      \n",
+      "\n",
+      "#Calculations\n",
+      "hfe=(deltaIc)/(deltaIb)\n",
+      "hoe=(deltaIc)/(deltaVce)\n",
+      "Rdc=Vcc/Ic                       #dc resistance(k ohms)\n",
+      "Rac=Vc/Ic1                       #ac resistance(k ohms)\n",
+      "Re=Rdc-Rac                       #emitter resistance(k ohms)\n",
+      "Rac1=(Rac*Rl)/(Rac+Rl)           #for load of 2kohms, Rc=Rac\n",
+      "Icq=Vcc/(Rac1+Rdc)               #Ic at operatingpoint(mA) \n",
+      "Vceq=Vcc-(Icq*Rdc)               #Vc at operating point(V)\n",
+      "\n",
+      "#Results\n",
+      "print\"value of hfe and hoe are\",hfe,\"uS and\",hoe,\"uS\"\n",
+      "print\"value Rc and Re are\",Rac,\"k ohms and\",Re,\"k ohms resp.\"\n",
+      "print\"value of Icq and Vce\",Icq,\"mA and\",Vceq,\"V resp.\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        " value of hfe and hoe are 100 uS and 500 uS\n",
+        "value Rc and Re are 1 k ohms and 1 k ohms resp.\n",
+        "value of Icq and Vce 6.0 mA and 4.0 V resp.\n"
+       ]
+      }
+     ],
+     "prompt_number": 8
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.29,Page number 200"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "hfe=120              #current gain\n",
+      "r1=1.5               #resistance(k ohms)\n",
+      "Vi=1                 #input voltage(V) \n",
+      "hoe=50*10**-3        #output conductance with input open circuited\n",
+      "Rs=2                 #source resistance(k ohms)\n",
+      "Vbe=0.7              #base to emitter voltage(V)\n",
+      "Vcc=10               #supply voltage(V)\n",
+      "r3=0.33              #resistance(k ohms)\n",
+      "r4=5.8               #rsistance(k ohms) \n",
+      "r5=27                #rsistance(k ohms) \n",
+      "hoe=50*10**-3        #output conductance with input open circuited\n",
+      "    \n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Vbb=Vcc*(r4/(r4+r5))          #voltage to bae(V)\n",
+      "Rb=(r5*r4)/(r5+r4)            # as Vbb-Vbe=RbIb+(hfe+1)Ib*R,here hfe=beeta\n",
+      "ib=(Vbb-Vbe)/(Rb+(hfe+1)*r3)  #instantaneous base current(mA)\n",
+      "hie=(0.02/ib)*10**3           \n",
+      "Ib=Vi/hie                    #base current(mA)\n",
+      "h=hfe*Ib\n",
+      "Avo=-h*r1                    #voltage gain\n",
+      "\n",
+      "#Part b\n",
+      "r=1/hoe                #resistance(k ohms)\n",
+      "R1=(r*r1)/(r+r1)       #resitance(k ohms)\n",
+      "R=(R1*Rs)/(R1+Rs)      #resistance(k ohms)\n",
+      "Ib1=1/(Rs+R)          #base current(mA)\n",
+      "h1=hfe*Ib1\n",
+      "Avl=-h1*R             #voltage gain\n",
+      "\n",
+      "#Results\n",
+      "print\"hie and Avo are\",round(hie),\"and\",round((Avo/1E-3),1)\n",
+      "print\"Avl is\",round(Avl,2)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "hie and Avo are 837.0 and -215.1\n",
+        "Avl is -34.95\n"
+       ]
+      }
+     ],
+     "prompt_number": 20
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.30,Page number 201"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Rl=20              #load resistance(ohms)\n",
+      "Vcc=30             #supply voltage(V)\n",
+      "beeta=150          #current gain \n",
+      "Re=2200            #emitter resistance(ohms)  \n",
+      "Rb=350             #base resistance(k ohms) \n",
+      "Vbe=0.7            #base to emitter voltage(V)\n",
+      "Is=10**-3          #source current(A) \n",
+      "r1=2000            #resistance(ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "Ib=(Vcc-Vbe)/(Rb+(1+beeta)*Re)#base current(uA)\n",
+      "Ic=beeta*Ib                   #collector current(mA)\n",
+      "rpi=beeta*(25/Ic)             #dynamic resistance(ohms)   \n",
+      "R=(Re*Rl)/(Re+Rl)             #resistance(ohms)  \n",
+      "Ib1=17.95                     #round the base emitter(as Rb>>2 kohms,it it ignored)\n",
+      "Vl=(beeta+1)*Ib1*R            #load voltage(V)\n",
+      "Avl=Vl                              #Voltage gain\n",
+      "Il=Vl/Rl                            #load current(A)\n",
+      "Ail=Il/Is                           #current gain\n",
+      "\n",
+      "#Results\n",
+      "print\"overall voltage gain is\",round((Avl/1E+3),2)\n",
+      "print\"overall current gain is\",round(Ail/1E+3)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "overall voltage gain is 51.5\n",
+        "overall current gain is 2575.0\n"
+       ]
+      }
+     ],
+     "prompt_number": 34
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 3.31,Page number 202"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vcc=15             #supply voltage(V)\n",
+      "beeta=30           #current gain \n",
+      "R=.47            #emitter resistance(ohms)  \n",
+      "Vbe=0.7            #base to emitter voltage(V)\n",
+      "Vo=5               #output voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "Vbb=Vcc/2                                   #base voltage(V)\n",
+      "'''\n",
+      "Vbb=(R1/2)*Ib+Vbe*2+(30Ib+Ic2)*R\n",
+      "Ic2=beeta*30Ib,so\n",
+      "Ic2=30*30Ib=900Ib\n",
+      "Vbb=(R1/2)*Ib+Vbe*2+(30+900)*R*Ib....(i)\n",
+      "(R1/2)*Ib+437*Ib=6.1.......(ii)\n",
+      "0.47*930Ib=5         #output voltage is given like this\n",
+      "\n",
+      "'''\n",
+      "Ib=Vo/(R*930)    #from equation(i)\n",
+      "\n",
+      "'''\n",
+      "substituting value of Ibin eq(ii) we get\n",
+      "\n",
+      "'''\n",
+      "R1=((6.1-4.98)/0.0114)*2                     #resistance(k ohms)  \n",
+      "#Results\n",
+      "print\"value of R1 is\",round(R1),\"K ohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "value of R1 is 196.0 K ohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 9
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Electronics_Devices_And_Circuits/chapter4.ipynb b/Electronics_Devices_And_Circuits/chapter4.ipynb
new file mode 100755
index 00000000..deab8d1e
--- /dev/null
+++ b/Electronics_Devices_And_Circuits/chapter4.ipynb
@@ -0,0 +1,1211 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:b257ecc13b812bf0b848ecef8624701db73088f3de1f9b82ca153fc8113f8c8b"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "     Chapter 4:           SMALL SIGNAL AMPLIFIERS-FREQUENCY RESPONSE"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.1,Page number 217"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Vs=1.               #source voltage(V)\n",
+      "C=100*10**-6        #value of capacitance(uF)  \n",
+      "r1=1                #resistance 1(k ohms)\n",
+      "r2=4                #resistance 2(k ohms)\n",
+      "R=5                 #total resistance,R=r1+r2\n",
+      "\n",
+      "#Calculations\n",
+      "Imax=Vs/(r1+r2)*10**3        #maximum current(uA)\n",
+      "fc=1/(2*(math.pi)*C*R)        #critical frequency(Hz) \n",
+      "                             #As w*C*R=1 and w=2*pi*f\n",
+      "f=10*fc                      #lowest frequency(Hz)\n",
+      "\n",
+      "#Results\n",
+      "print\"maximum current\",Imax,\"uA\"\n",
+      "print\"critical frequency\",round((fc/1E+3),3),\"Hz\"\n",
+      "print\"lowest frequency\",round((f/1E+3),2),\"Hz\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "maximum current 200.0 uA\n",
+        "critical frequency 0.318 Hz\n",
+        "lowest frequency 3.18 Hz\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.2,Page number 218"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "C=100*10**-6     #capacitance(uF)\n",
+      "Rg=1.            #galvanometer resistance(k oms)\n",
+      "Rl=4.            #load resistance(k ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "Rth=(Rg*Rl)/(Rg+Rl)      #thevinine's equivalent resistance\n",
+      "fc=1/(2*(math.pi)*C*Rth)  #critical frequency(Hz)\n",
+      "f=fc*C                    #lowest frequency(Hz)\n",
+      "\n",
+      "#Results\n",
+      "print\"lowest frequency at which the point A gets grounded is\",round((f/1E-2),1),\"Hz\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "lowest frequency at which the point A gets grounded is 19.9 Hz\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.3,Page number 220"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "rpi=600               #dynamic junction resistance(ohms)\n",
+      "beta=100              #common emitter current gain\n",
+      "Vs=5.                 #source voltage(V)\n",
+      "Rs=400                #source resistance(ohms)\n",
+      "R=10                  #resistance(k ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "Ib=Vs/(Rs+rpi)       #base current(uA)  \n",
+      "Vo=R*beeta*Ib        #output voltage(V)\n",
+      "Rin=rpi              #input resistance(ohms)\n",
+      "Rout=R               #output ewsistance(k ohms)\n",
+      "\n",
+      "#Results\n",
+      "print\"output voltage is\",Vo,\"V\"\n",
+      "print\"input resistance\",Rin,\"ohms\"\n",
+      "print\"output resistance\",Rout,\"k ohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "output voltage is 5.0 V\n",
+        "input resistance 600 ohms\n",
+        "output resistance 10 k ohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 12
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.4,Page number 220"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "gm=1.                    #transconductance(mS)\n",
+      "rd=40                    #dynamic drain resistance(k ohms)  \n",
+      "Rd1=40                   #JFET 1 drain resistance(k ohms) \n",
+      "Rd2=10                   #JFET 2 drain resistance(k ohms) \n",
+      "\n",
+      "#Calculations\n",
+      "Avo=(-gm*((rd*Rd1)/(rd+Rd1)))*(-gm*((rd*Rd2)/(rd+Rd2)))             #voltage gain\n",
+      "\n",
+      "#Results\n",
+      "print\"Avo is\",Avo"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Avo is 160.0\n"
+       ]
+      }
+     ],
+     "prompt_number": 19
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.5,Page number 222"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "beta=125           #common emitter current gain\n",
+      "rpi=2.5            #dynamic junction resistance(k ohms)\n",
+      "rd=40              #dynamic drain resistance(k ohms)   \n",
+      "gm=2               #transconductance(mS) \n",
+      "Vs=1               #assume,source voltage(V)\n",
+      "Rs=10              #source resistance(k ohms)\n",
+      "Rc=1               #collector resistance(k ohms)\n",
+      "rb=2               #resistance(k ohms)\n",
+      "Vgs=1              #gate to source voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "R=(rd*Rs)/(rd+Rs)      #equivalent resistance(k ohms)\n",
+      "Ib=gm*Vgs*(R/(rpi+R))  #base current(mA)\n",
+      "Vo=beeta*Ib*Rc         #output voltage(V)   \n",
+      "Avo=Vo                 #voltage gain\n",
+      "\n",
+      "#Part b\n",
+      "Ib1=Vs/(rb+rpi)        #base current(mA) after interchanging stages of JFET and BJT  \n",
+      "Vgs1=beeta*Ib1*Rc      #gate to source voltage(V) after interchanging stages of JFET and BJT\n",
+      "Vo1=gm*Vgs1*R          #output voltage(V) after interchanging stages of JFET and BJT\n",
+      "Avo1=Vo1               #voltage gain after interchanging stages of JFET and BJT\n",
+      "\n",
+      "#Results\n",
+      "print\"Avo is\",round(Avo,1)\n",
+      "print\"Avo1 when BJT and FET stages are reversed is\",round(Avo1)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Avo is 190.5\n",
+        "Avo1 when BJT and FET stages are reversed is 444.0\n"
+       ]
+      }
+     ],
+     "prompt_number": 24
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.6,Page number 226"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Cc1=1*10**-6                 #coupling capacitor 1(uF)\n",
+      "Cc2=1*10**-6                 #coupling capacitor 2 (uF)  \n",
+      "Rs=10**3                     #source resistance(k ohms)\n",
+      "rpi=2*10**3                  #dynamic junction resistance(k ohms)\n",
+      "Rc=4500                      #collector resistance(ohms)\n",
+      "Rl=9*10**3                   #load resistance(k ohms)\n",
+      "w=100                        #corner frequency(rad/s)\n",
+      "\n",
+      "#Calculations\n",
+      "w11=1/(Cc1*(Rs+rpi))                    #corner frequency input circuit (rad/s)\n",
+      "w12=1/(Cc2*(Rc+Rl))                     #corner frequency output circuit(rad/s)\n",
+      "f=w11/(2*(math.pi))                     #lower cutoff frequency(Hz)\n",
+      "Zin=complex((Rs+rpi),-(1/(w*Cc1)))      #input impedance(k ohms)   \n",
+      "Zout=complex(Rc,-(1/(w*Cc2)))           #output impedance(k ohms)   \n",
+      "\n",
+      "#Results\n",
+      "print\"lower cut-off freq is\",round(f),\"Hz\"\n",
+      "print\"Zin\",Zin,\"ohms\"\n",
+      "print\"Zout\",Zout,\"ohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "lower cut-off freq is 53.0 Hz\n",
+        "Zin (3000-10000j) ohms\n",
+        "Zout (4500-10000j) ohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 37
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.7,Page number 229"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Re=Rc=1.5*10**3              #collector resistance(ohms)\n",
+      "Rs=600                       #source resistance(ohms)\n",
+      "Rl=2*10**3                   #load resistance(ohms)  \n",
+      "beeta=100                     #common emitter current gain \n",
+      "rpi=1*10**3                  #dynamic junction resistance(ohms)\n",
+      "f=50                         #frequency(Hz)\n",
+      "\n",
+      "#Calculations\n",
+      "w=2*f*(math.pi)              #corner frequency(rad/s)\n",
+      "CE=1/(w*(Rs+rpi))            #capacitance(uF)\n",
+      "Ce=CE*(beeta+1)              #capacitance(uF)\n",
+      "w11=w/10                     #corner frequency input circuit (rad/s)\n",
+      "w12=w11/20                   #corner frequency output circuit(rad/s)\n",
+      "Cc1=1/(w11*(Rs+rpi))         #coupling capacitor 1(uF)  \n",
+      "Cc2=1/(w12*(Rc+Rl))          #coupling capacitor 2 (uF)  \n",
+      "\n",
+      "#Results\n",
+      "print\"Ce is\",round(Ce/1E-6),\"uF\"\n",
+      "print\"Cc1 is\",round(Cc1/1e-6,1),\"uF\"\n",
+      "print\"Cc2 is\",round((Cc2/1E-5),2),\"uF\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Ce is 201.0 uF\n",
+        "Cc1 is 19.9 uF\n",
+        "Cc2 is 18.19 uF\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.8,Page number 235"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "gm=2.5*10**-3            #transconductance(mS) \n",
+      "Rd=6*10**3               #drain resistance(ohms)\n",
+      "rd=200*10**3             #dynamic drain resistance(ohms)   \n",
+      "Cc1=Cc2=0.12*10**-6      #coupling capacitors(uF)\n",
+      "Rs=1*10**3               #source resistance(ohms)\n",
+      "Rg=0.1*10**6             #R1||R2  \n",
+      "Cgs=12*10**-9            #gate to source capacitor(pF) \n",
+      "Cgd=2*10**-9             #gate to drain capacitor(pF)    \n",
+      "Co1=10                   # as Co1=Cl+Cw=10\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Ro=(rd*Rd)/(rd+Rd)                  #equivalent resistance of rd and Rd(ohms)\n",
+      "Vo=-gm*((rd*Rd)/(rd+Rd))            #as Vgs=Vs\n",
+      "Avo=Vo                              #Avo=Vo/Vs=(-gm*Vs*((rd*Rd)/(rd+Rd)))/Vs=Vo  \n",
+      "    \n",
+      "#Part b\n",
+      "f11=1/(2*(math.pi)*Cc1*(Rs+Rg))\n",
+      "\n",
+      "#Part c\n",
+      "Ceq=Cgs+(Cgd*(1+gm*Ro))                    #on application of miller theorem\n",
+      "Co=Co1+Cgd*(1+(1/(gm*Ro)))                 #output capacitance(pF)\n",
+      "f21=1/(2*(math.pi)*Ceq*((Rs*Rg)/(Rs+Rg)))  #input circuit cutoff frequency(MHz)\n",
+      "f22=1/(2*(math.pi)*Co*Ro)*10**3            #output circuit cutoff frequency(MHz)\n",
+      "fH=f22                                     #cutoff frequency of high frequency band(MHz)\n",
+      "\n",
+      "#Results\n",
+      "print\"a)mid freq gain is\",round(Avo,1)\n",
+      "print\"b)input circuit cut-off is\",round(f11,1),\"Hz\"\n",
+      "print\"c)high freq input cutoff is\",round((f21/1E+3),2),\"and output cutoff is\",round((f22/1E-3),2),\"MHz\"\n",
+      "print\"high freq cut-off is\",round((fH/1E-3),2),\"MHz\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)mid freq gain is -14.6\n",
+        "b)input circuit cut-off is 13.1 Hz\n",
+        "c)high freq input cutoff is 3.73 and output cutoff is 2.73 MHz\n",
+        "high freq cut-off is 2.73 MHz\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.9,Page number 238"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "beta=50.              #common emitter current gain \n",
+      "R1=11.5              #resistance(k ohms)\n",
+      "R2=41.4              #resistance(k ohms)  \n",
+      "Vcc=10.               #supply voltage to collector(V)\n",
+      "Rc=5.                 #collector resistance(k ohms)\n",
+      "Re=1.                 #emitter resistance(k ohms)\n",
+      "Rs=1.                 #source resistance(k ohms)\n",
+      "Vbe=0.7              #base emitter voltage(V)\n",
+      "Rl=10.                #load resistance(k ohms)\n",
+      "Cc1=Cc2=20*10**-6.    #coupling capacitors(uF)\n",
+      "Ce=150*10**-6.        #emitter capacitor(uF)  \n",
+      "Cpi=100       \n",
+      "Cu=5.\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Rb=(R1*R2)/(R1+R2)                 #R1||R2(k ohms)\n",
+      "Vbb=Vcc*(R1/(R1+R2))               #suply voltage to base(V)\n",
+      "Ib=(Vbb-Vbe)/(Rb+(Rs*(1+beta)))   #base current(mA)\n",
+      "Ic=beta*Ib                        #collector current(mA)  \n",
+      "Vce=Vcc-(Ic*Rc)-(Ic+Ib)*Re         #collector to emitter voltage(V) \n",
+      "rpi=(25*beta)*10**-3/Ic                  #dynamic junction resistance(K ohms) \n",
+      "    \n",
+      "#Part b\n",
+      "rpi=1                              #dynamic junction resistance(K ohms)  \n",
+      "R=(rpi*Rb)/(rpi+Rb)                #equivalent resistance(rpi||Rb) \n",
+      "Vbe=(R*Rs)/(R+Rs)                  #base to emitter voltage(V)\n",
+      "Ib1=Vbe/rpi                        #base current(mA)\n",
+      "Ro=(Rc*Rl)/(Rc+Rl)                 #Rc||Rl(k ohms)   \n",
+      "Vo=-(beta*Ib1*Ro)                 #output voltage(V)\n",
+      "Avo=Vo                             #voltage gain\n",
+      "\n",
+      "#Part c\n",
+      "r1=(Rs*Rb)/(Rs+Rb)                #Rs||Rb(k ohms) \n",
+      "w11=1/(Cc1*(Rs+R))                #low freq cutoff(rad/s)\n",
+      "w12=1/(Cc2*(Rc+Rl))               #high freq cutoff(rad/s) \n",
+      "w1p=1/((Ce/(beta+1))*(r1+rpi))   #low cutoff freq(rad/s)\n",
+      "\n",
+      "#Part d\n",
+      "Co1=5                          #as Co1=Cw+Cl\n",
+      "gm=beta/rpi                    #transconductance(mS)    \n",
+      "Ceq=Cpi+(Cu*(1+(gm*Ro)))   #equivalent capacitance(pF)\n",
+      "Rs1=(Rb*Rs)/(Rb+Rs)            #Rb||Rs(k ohms)\n",
+      "r2=(Rs1*rpi)/(Rs1+rpi)         #Rs1||rpi(k ohms)\n",
+      "w21=10**12/(Ceq*r2*10**3)                 #low freq cutoff(MHz) \n",
+      "\n",
+      "#Results\n",
+      "print\"a)dc bias values are Vbb:\",round(Vbb,2),\"V, Ib:\",round(Ib,4),\"mA, Ic:\",round(Ic,2),\"mA, Vce:\",round(Vce,3),\"V, rpi:\",rpi,\"k ohms\"\n",
+      "print\"mid freq gain is\",round(Avo,2)\n",
+      "print\"low freq cut-off is\",round(w1p/1E+3),\"rad/s\"\n",
+      "print\"high cut-off freq is\",round((w21/1E+6),2),\"*10**6 rad/s\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)dc bias values are Vbb: 2.17 V, Ib: 0.0246 mA, Ic: 1.23 mA, Vce: 2.606 V, rpi: 1 k ohms\n",
+        "mid freq gain is -78.95\n",
+        "low freq cut-off is 179.0 rad/s\n",
+        "high cut-off freq is 2.25 *10**6 rad/s\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.10,Page number 243"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Qcoil=75.               #coil inductance\n",
+      "f=200.                  #frequency(Hz) \n",
+      "BW=4.                   #bandwidth(kHz)\n",
+      "C=470*10**-9.           #capacitance(pF) \n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Qcircuit=f/BW                     #circuit inductance\n",
+      "L=1/(((2*(math.pi)*f)**2)*C)      #inductance(mH)  \n",
+      "\n",
+      "#Part b\n",
+      "R=Qcircuit*2*(math.pi)*f*L        #resistance(k ohms)\n",
+      "\n",
+      "#Part c\n",
+      "r=(2*(math.pi)*f*L)/Qcoil         #internal resistance(ohms)\n",
+      "req=(Qcoil**2)*r                  #equivalent resistance(k ohms)\n",
+      "ro=(R*req)/(req-R)                #output resistance(k ohms)\n",
+      "\n",
+      "#Part d\n",
+      "BW=5                               #bandwidth(kHz)\n",
+      "Qcircuit=f/BW                      #circuit inductance \n",
+      "Req=Qcircuit*2*(math.pi)*f*L       #equivalent resistance(k ohms) \n",
+      "Rl=(Req*R)/(R-Req)                 #load resistance(k ohms)\n",
+      "\n",
+      "#Results\n",
+      "print\"a)coil inductance is\",round(L,2),\"mH\"\n",
+      "print\"b)circuit output impedance atresonant freq is\",round((R/1E+3),2),\"K ohms\"\n",
+      "print\"c)internal resistance ro is\",round((ro/1E+3),2),\"k ohms\"\n",
+      "print\"d)value of load resistance is\",round((Rl/1E+3),2),\"k ohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)coil inductance is 1.35 mH\n",
+        "b)circuit output impedance atresonant freq is 84.66 K ohms\n",
+        "c)internal resistance ro is 253.97 k ohms\n",
+        "d)value of load resistance is 338.63 k ohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.11,Page number 246"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "fo=50                           #output frequency(KHz)\n",
+      "L=10**-3                        #inductance(H)  \n",
+      "ro=100                          #output resistance(k ohms)\n",
+      "Q=80                            #coil inductance\n",
+      "Ri=10                           #input resistance(k ohms)\n",
+      "beta=125                        #common emitter current gain \n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "C =1/(((2*(math.pi)*fo)**2)*L)   #tunning capacitance(nF)\n",
+      "r=(2*(math.pi)*fo*L)/Q           #internal resistance(k ohms)\n",
+      "req=(Q**2)*r                     #equivalent resistance(k ohms) \n",
+      "R=(ro*req)/(ro+req)              #ro||req(k ohms)\n",
+      "Avo=-(beta*R)/Ri                 #voltage gain\n",
+      "\n",
+      "#Part b\n",
+      "Qcircuit=R/(2*(math.pi)*fo*L)    #circuit inductance\n",
+      "BW=fo/Qcircuit                   #bandwidth\n",
+      "\n",
+      "#Results\n",
+      "print\"a)value of capacitance is\",round(C/1E-3),\"nF\"\n",
+      "print\"  gain is\",round(Avo,1)\n",
+      "print\"b)bandwidth is\",round(BW/1E-3),\"Hz\",\"(value used for beta in texbook is wrong in the solution)\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)value of capacitance is 10.0 nF\n",
+        "  gain is -251.1\n",
+        "b)bandwidth is 782.0 Hz (value used for beta in texbook is wrong in the solution)\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.12,Page number 248"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "\n",
+      "f=1*10**6                  #radio frequency(Hz)\n",
+      "beta=50                    #common emitter current gain \n",
+      "fT=5*10**6                 #short circuit current gain bandwidth product(Hz)\n",
+      "\n",
+      "#Calculations\n",
+      "betaf=fT/f                 #measurement of short circuit current gain\n",
+      "fbeta=fT/beta              #frequency at beta(Hz)\n",
+      "\n",
+      "#Results\n",
+      "print\"frequency is\",fbeta,\"Hz\"\n",
+      "if fbeta<1*10**6:\n",
+      "    print\"transistor is not suitable for 1Mhz amplifier as fbeta is less than 1Mhz\"\n",
+      "else:\n",
+      "    print\"transistor is suitable for 1Mhz amplifier\"\n",
+      "    "
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "frequency is 100000 Hz\n",
+        "transistor is not suitable for 1Mhz amplifier as fbeta is less than 1Mhz\n"
+       ]
+      }
+     ],
+     "prompt_number": 15
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.13,Page number 249"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "rpi=2                     #dynamic junction resistance(K ohms)  \n",
+      "beta=50.                   #common emitter current gain \n",
+      "f=1                        #frequency(MHz)\n",
+      "beta1=2.5                  #common emitter current gain \n",
+      "f1=20*10**6                #frequency(Hz)\n",
+      "\n",
+      "#Calculations\n",
+      "fT=beta1*f1                  #short circuit current gain bandwidth product(Hz)\n",
+      "fbeta=fT/beta                #frequency at beta(Hz)\n",
+      "Cpi=1/(2*(math.pi)*fbeta*rpi)   #dynamic capacitance(pF)\n",
+      "\n",
+      "#Results\n",
+      "print\"fT is\",round(fT/1e+6),\"MHz\"\n",
+      "print\"fB is\",round(fbeta/1e+6),\"MHz\"\n",
+      "print\"Cpi is\",round(Cpi/1e-9),\"pF\"   "
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "fT is 50.0 MHz\n",
+        "fB is 1.0 MHz\n",
+        "Cpi is 80.0 pF\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.14,Page number 256"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "R1=60                 #resistance(k ohms)\n",
+      "R2=140                #resistance(k ohms)\n",
+      "Rs=4                  #source resistance(k ohms)\n",
+      "Re=3                  #emitter resistance(k ohms)\n",
+      "Rc=4                  #collector resistance(k ohms)\n",
+      "Vcc=10                #supply voltage to collector(V)\n",
+      "Vbe=0.7               #base to emitter voltage(V)\n",
+      "beta=100              #common emitter current gain \n",
+      "Avo=-30               #voltage gain \n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Rb=(R1*R2)/(R1+R2)                  #R1||R2(k ohms)\n",
+      "Vth=(Vcc*R1)/(R1+R2)                #thevinine's voltage(V)\n",
+      "Ib=(Vth-Vbe)/(Rb+(beta+1)*Re)       #base current(uA)\n",
+      "Ic=Ib*beta                          #collector current(mA) \n",
+      "Vce=Vcc-(Rc*Ic)-((beta+1)*Ib*Re)    #collector to emitter voltage(V)\n",
+      "\n",
+      "#Part b\n",
+      "rpi=((25*beta)/Ic)*10**-3         #dynamic junction resistance(k ohms)\n",
+      "r=(Rb*rpi)/(Rb+rpi)               #resistance across Vs\n",
+      "Ib1=r/((Rs+r)*rpi)                #base current(mA)\n",
+      "Rl=(-Rc*Avo)/(Avo+(beta*Ib1*Rc))  #load resistance(k ohms)\n",
+      "\n",
+      "#Results\n",
+      "print\"value of Ic and Vce are\",round(Ic,3),\"mA and\",round(Vce,2),\"V\"\n",
+      "print\"Rl is\",round(Rl,2),\"k ohms\"    "
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "value of Ic and Vce are 0.667 mA and 5.31 V\n",
+        "Rl is 6.21 k ohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 11
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.15,Page number 257"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "R1=25.                      #resistances(k ohms)\n",
+      "R2=100.                     #resistances(k ohms)\n",
+      "Re=2.                       #emitter resistance(k ohms) \n",
+      "Vcc=10.                     #supply voltage to collector\n",
+      "Vbe=0.7                    #base to emitter voltage(V)\n",
+      "beta=100.                   #common emitter current gain\n",
+      "Avo=160                    #voltage gain\n",
+      "Rs=1                       #source resistance(k ohms)\n",
+      "Vs=1                       #source voltage(V) \n",
+      "Rl=12.5                    #load resistance(k ohms)\n",
+      "Rc1=20.                     #collector resistance(k ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Rb=(R1*R2)/(R1+R2)              #R1||R2\n",
+      "Vth=(Vcc*R1)/(R1+R2)            #thevinines voltage(V)\n",
+      "Ib=(Vth-Vbe)/(Rb+(beta+1)*Re)   #base current(uA)\n",
+      "Ic=Ib*beta                      #collector current(mA)\n",
+      "rpi=(25*beta)*10**-3/Ic                #dynamic junction resistance(k ohms)\n",
+      "\n",
+      "#Part b\n",
+      "Ib1=1/rpi                       #small signal analysis \n",
+      "Rc=-Avo/(-beta*Ib1)             #collector resistance() \n",
+      "\n",
+      "#Part c\n",
+      "r=(Rc1*rpi)/(Rc1+rpi)              #Rc1||rpi1(k ohms) \n",
+      "Ib2=(Vs*r)/((1+r)*rpi)               #base curret(mA)\n",
+      "Rc2=6.84                             #collector resistance(k ohms)                                      \n",
+      "Avo=-(beta*Ib2)*((Rl*Rc2)/(Rl+Rc2))  #voltage gain\n",
+      "\n",
+      "#Results\n",
+      "print\"value of Ic\",round(Ic,3),\"mA and rpi is\",round(rpi,2),\"k ohms\"  \n",
+      "print\"Rc is\",round(Rc,2),\"k ohms\"\n",
+      "print\"Avo is\",round(Avo,1)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "value of Ic 0.586 mA and rpi is 4.27 k ohms\n",
+        "Rc is 6.83 k ohms\n",
+        "Avo is -80.6\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.16,Page number 258"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "R1=12.                 #resistance(k ohms)\n",
+      "R2=100.                #resistance(k ohms)\n",
+      "Rc=2                   #collector resistance(k ohms)\n",
+      "Ic=1.2                 #collector current(mA)\n",
+      "beta=60                #common emitter current gain\n",
+      "Ib1=1                  #(say)\n",
+      "Rs=1                   #source resistance(k ohms)\n",
+      "Vs=1                   #source vcoltage(say)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "rpi=((25*beta)/Ic)*10**-3     #dynamic junction resistance(k ohms)\n",
+      "Rb=(R1*R2)/(R1+R2)            #R1||R2(k ohms)\n",
+      "r=(Rb*rpi)/(Rb+rpi)           #Rb||rpi(k ohms)\n",
+      "Ro1=(Rc*rpi)/(Rc+rpi)         #Rc||rpi(k ohms)\n",
+      "Vo1=Vbe2=-(beta*Ib1*Ro1)      #base to emitter voltage(V)\n",
+      "Ib2=Vo1/rpi                   #base current(mA)\n",
+      "Ai=Ib2/Ib1                    #current gain \n",
+      "\n",
+      "#Part b\n",
+      "Ib11=(Rs*r)/((Rs+r)*rpi)          #base currents(mA)\n",
+      "Ib21=Ib11*Ai                #base current(mA)\n",
+      "Avo1=Vo1=Ib21*rpi           #voltage gain\n",
+      "\n",
+      "#Results\n",
+      "print\"current gain is\",round(Ai,2)\n",
+      "print\"overall voltage gain is\",round(Avo1,2),\"(solution in the textbook is incorrect)\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "current gain is -36.92\n",
+        "overall voltage gain is -19.5 (solution in the textbook is incorrect)\n"
+       ]
+      }
+     ],
+     "prompt_number": 5
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.17,Page number 259"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "beeta=50.                 #common emitter current gain\n",
+      "R1=25.                   #resistance(k ohms)\n",
+      "R2=75.                   #resistance(k ohms)\n",
+      "Ic=1.25                  #collector current(mA)\n",
+      "Vcc=10                   #supply voltage to collector(V)\n",
+      "s=10*10**-3              #signal strength(V)\n",
+      "Rs=0.5                  #output impedance(k ohms)\n",
+      "Vo=1                    #output voltage(V)\n",
+      "Vs=1.                    #source voltage(V) \n",
+      "Vl=12                   #load at output terminal(Vl)\n",
+      "Vbe=0.7                 #base to emitter voltage(V)\n",
+      "Rl=12\n",
+      "\n",
+      "#Calculations\n",
+      "rpi=((25*beeta)/Ic)              #dynamic junction resistance(k ohms)\n",
+      "Rb=(R1*R2)/(R1+R2)               #R1||R2(k ohms)\n",
+      "r=(Rb*rpi*10**-3)/(Rb+rpi*10**-3)              #Rb||rpi(k ohms)\n",
+      "Avo=((Vo*rpi)/Vcc)                     #voltage gain\n",
+      "Ib=(r*Vs)/(Rs+r)*Vs                    #base current(mA)\n",
+      "Rc=(Rl*Avo)/(beeta*Ib*Rl-Avo)          #collector resistance(k ohms)\n",
+      "Vth=(Vcc*R1)/(R1+R2)                   #thevinine's voltage(V)\n",
+      "Ib1=Ic/beeta                           #base current(mA)\n",
+      "Re=(Vth-Vbe-(Rb*Ib1))/((beeta+1)*Ib1)    #emitter resistance(k ohms) \n",
+      "\n",
+      "#Results\n",
+      "print\"value of Rc is\",round(Rc,2),\"and Re is\",round(Re,2),\"k ohms (Vth value is wrong substituted in the book)\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "value of Rc is 4.1 and Re is 1.04 k ohms (Vth value is wrong substituted in the book)\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.18,Page number 260"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Cpi=20*10**-9           #opening capacitor(F)\n",
+      "Cu=5*10**-9  \n",
+      "C=50*10**-9             #here C=Cl+Cw\n",
+      "rpi=3.75*10**3          #dynamic drain resistance(ohms)\n",
+      "r1=4*10**3              #resistance(ohms)\n",
+      "r2=42*10**3             #resistance(ohms)\n",
+      "r3=303*10**3            #resistance(ohms)\n",
+      "f=20                    #frequency(Hz)\n",
+      "beeta=100               #common emitter current gain\n",
+      "Rl=10*10**3             #load resistance(ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Req=(((r1*r2)/(r1+r2)+rpi)*r3)/(((r1*r2)/(r1+r2)+rpi)+r3)    #equivalent resistance(ohms)\n",
+      "Ce=(beeta+1)/(2*(math.pi)*f*Req)                             #emitter capacitance(uF)\n",
+      "\n",
+      "#Part b\n",
+      "gm=beeta/rpi                   #transconductance\n",
+      "Ro=(Rl*r1)/(r1+Rl)             #output resistance(k ohms)\n",
+      "Ceq=Cpi+(Cu*(1+gm*Ro))         #equivalent capacitance(pF)\n",
+      "Co=C+(Cu*(1+(1/(gm*Ro))))      #output capacitance(pF)\n",
+      "r=(rpi*r1)/(rpi+r1)            #rpi||r1\n",
+      "w21=1/(Ceq*r)                  #lower cutoff frequency(MHz)\n",
+      "w22=1/(Co*Ro)                  #higher cutoff frequenct(MHz)\n",
+      "\n",
+      "#Part c\n",
+      "Ceqnew=Cpi+(Cu*(1+(0.75*(gm*Ro))))           #as gain is reduced to 75% of original value\n",
+      "wHnew=(10**12)/(Ceqnew*r)                    #corner value of high frequency(Mrad/s)  \n",
+      "fHnew=wHnew/(2*(math.pi))                    #new value of higher frequency cutoff(KHz)\n",
+      "\n",
+      "#Results\n",
+      "print\"a)value of bypass capacitor Ce is\",round(Ce/1E-6),\"uF\"\n",
+      "if w21>w22:\n",
+      "       print\"higher frequency is w21\"\n",
+      "else:\n",
+      "    print\"higher frequency is w22\"\n",
+      "\n",
+      "print\"b)high frequency cut-off is\",round((w22/1E+3),2),\"Mrad/s\"\n",
+      "print\"c)high frequency cut-off is\",fHnew,\"Hz\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)value of bypass capacitor Ce is 111.0 uF\n",
+        "higher frequency is w22\n",
+        "b)high frequency cut-off is 6.36 Mrad/s\n",
+        "c)high frequency cut-off is 2.64660617737e+14 Hz\n"
+       ]
+      }
+     ],
+     "prompt_number": 36
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.19,Page number 262"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Vcc=3.                     #supply voltage to collector(V)\n",
+      "Vee=-3.                    #supply voltage to emitter(V)\n",
+      "r1=40.                     #resistance(ohms) \n",
+      "r2=25.                     #resistance(ohms)\n",
+      "r3=1.56                    #resistance(ohms)\n",
+      "Vs=3.                      #source voltage(V)\n",
+      "beeta=200                  #common emitter current gain\n",
+      "r4=0.6                     #resistance(ohms)\n",
+      "r5=0.15                    #resistance(ohms)\n",
+      "Vbe=0.7                    #base to emitter voltage\n",
+      "r=0.5                      #resistance(k ohms)\n",
+      "fL=20                      #frequency(Hz)\n",
+      "Req1=24.24                 #solving r||(Rth+rpi+R)||Re\n",
+      "f=2                        #non dominant cutoff freq is fL/10 i.e 20/10\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Vth=Vs-(((Vcc-Vee)/(r1+r2))*r1)             #thevinine's voltage(V)\n",
+      "Rth=(r1*r2)/(r1+r2)                         #thevinine's voltage(V)\n",
+      "Ib=(Vth-Vbe+Vcc)/(Rth+((r4+r5)*(beeta+1)))  #base current(mA)\n",
+      "Ic=Ib*beeta                                 #Collector current(mA)  \n",
+      "Vo=Vcc-(r3*Ic)                              #output voltage(V)\n",
+      "\n",
+      "#Part b\n",
+      "rpi=(25*beeta)/Ic                          #dynamic drain resistance(ohms)\n",
+      "R=r4*(beeta+1)                             #resistance(k ohms)\n",
+      "ro=(rpi*R)/(rpi+R)                         #rpi||R(k ohms)\n",
+      "Req=r+((Rth*ro)/(Rth+ro))                  #equivalent resistance(k ohms) \n",
+      "Cc1=1/(Req*2*(math.pi)*fL)                 #coupling capacitor(uF)\n",
+      "\n",
+      "#Part c\n",
+      "Ce=1/(2*(math.pi)*fL*Req1)                #emitter capacitance(uF)\n",
+      "CE=beeta*Ce                               #emitter capacitance(uF) after current gain\n",
+      "\n",
+      "#Part d\n",
+      "Ce1=1/(2*(math.pi)*f*Req1)              #emitter capacitance(uF)\n",
+      "CE1=beeta*Ce1                           #emitter capacitance(uF) after current gain\n",
+      "Csum=Cc1+CE1                            #total capacitance(uF)\n",
+      "\n",
+      "#Results\n",
+      "print\"a)Ic and Vo are\",round(Ic,2),\"mA and\",round(Vo),\"V\"\n",
+      "print\"b)Cc1 is\",round((Cc1/1E-3),3),\"uF\"\n",
+      "print\"c)Ce is\",round((CE/1E-3),1),\"uF\"\n",
+      "print\"d)Csum is\",round((Csum/1E-2),3),\"uF\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)Ic and Vo are 1.94 mA and -0.0 V\n",
+        "b)Cc1 is 0.565 uF\n",
+        "c)Ce is 65.7 uF\n",
+        "d)Csum is 65.715 uF\n"
+       ]
+      }
+     ],
+     "prompt_number": 33
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.21,Page number 265"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "gm=2                   #transconductance\n",
+      "rd=200*10**3           #dynamic drain resistance(ohms)\n",
+      "Cgs=10                 #gate to source capacitance(pF)\n",
+      "Cgd=0                  #gate to drain capacitance(pF)\n",
+      "Rs=1*10**3             #source resistance(ohms)\n",
+      "Rg=1*10**6             #Rg=R1||R2\n",
+      "Rd=5*10**3             #drain resistance(ohms) \n",
+      "Rs1=2                  #resistance(k ohms) \n",
+      "Cc1=Cc2=0.1*10**-6     #coupling capacitors(F)\n",
+      "Co=10*10**-12          #output capacitance(F)\n",
+      "Vgs=1                  #gate to source voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "R=(Rd*rd)/(Rd+rd)     #Rd||rd(k ohms)\n",
+      "Avo=Vo=-Vgs*gm*R      #voltage gain\n",
+      "\n",
+      "#Part b\n",
+      "w11=1/(Cc1*(Rs*Rg))           #corner freq(rad/s)\n",
+      "wL=w11                        #input circuit corner freq(rad/s)\n",
+      "\n",
+      "#Part c\n",
+      "w22=10**12/((Cgs*R)*10**3)     #output circuit corner frequency(rad/s)\n",
+      "wH=w22/(2*math.pi)                          \n",
+      "\n",
+      "#Part d\n",
+      "G=-Avo*wH                         #gain bandwidth product\n",
+      "\n",
+      "#Part e\n",
+      "Rd=4*10**3                      #drain resistance reduced(ohms) \n",
+      "Rnew=(Rd*rd)/(Rd+rd)            #new resistance(ohms)\n",
+      "Avo1=-Vgs*gm*Rnew               #new voltage gain\n",
+      "BWnew=(10**8/Rnew)/(2*math.pi)                #new bandwidth(Mrad/s)\n",
+      "Gnew=-Avo1*BWnew                 #gain bandwidth product new\n",
+      "\n",
+      "#Results\n",
+      "print\"a)Avo is\",round((Avo/1E+3),2)\n",
+      "print\"b)wL is\",round((wL/1E-3),2),\"rad/s\"\n",
+      "print\"c)wH is\",round((wH/1E+3),1),\"MHz\"\n",
+      "print\"d)G is\",round((G/1E+6),2),\"MHz\"\n",
+      "print\"e)Gnew is\",round((Gnew/1E+6),1),\"MHz\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)Avo is -9.76\n",
+        "b)wL is 10.0 rad/s\n",
+        "c)wH is 3.3 MHz\n",
+        "d)G is 31.83 MHz\n",
+        "e)Gnew is 31.8 MHz\n"
+       ]
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 4.23,Page number 268"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "gm=1                    #transconductance\n",
+      "rd=40                   #dynamic drain resistance(k ohms) \n",
+      "Cgs=5                   #gate to source capacitance(pF)\n",
+      "Cgd=1                   #gate to drain capacitance(pF)\n",
+      "Cds=1                   #drain to source capacitance(pF)\n",
+      "Avo1=20.                #voltage gain of JFET 1\n",
+      "Avo2=8.                 #voltage gain of JFET 2 \n",
+      "R1=5                    #resistance(k ohms)\n",
+      "R2=20                   #resistance(k ohms)\n",
+      "R3=8                    #resistance(k ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Avo=Avo1*Avo2               #voltage gain\n",
+      "Ceq1=Cgs+Cgd*(1+Avo1)       #input crcuit for first JFET\n",
+      "Co1=Cds+(Cgd*(1+(1/Avo1)))  #output crcuit for first JFET\n",
+      "Ceq2=Cgs+Cgd*(1+Avo2)       #input crcuit for second JFET\n",
+      "Co2=Cds+(Cgd*(1+(1/Avo2)))  #output crcuit for second JFET\n",
+      "\n",
+      "#Part b\n",
+      "w21=1/(R1*Ceq1)             #input circuit frequency\n",
+      "w2=10**12/(R2*10**3*(Co1+Ceq2))        #common circuit frequency\n",
+      "w22=1/(R3*Co2)              #output circuit frequency\n",
+      "\n",
+      "\n",
+      "#Results\n",
+      "print\"a)Avo is\",Avo\n",
+      "print\"b)w21,w2,w22 are\",round((w21/1E-3),2),\"Mrad/sec,\",round((w2/1E+6),2),\"Mrad/sec and\",round((w22/1E-3),2),\"Mrad/sec\"\n",
+      "print\"nondominant corner freq is\",round((w2/1E+6),2),\"Mrad/sec\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)Avo is 160.0\n",
+        "b)w21,w2,w22 are 7.69 Mrad/sec, 3.12 Mrad/sec and 58.82 Mrad/sec\n",
+        "nondominant corner freq is 3.12 Mrad/sec\n"
+       ]
+      }
+     ],
+     "prompt_number": 21
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Electronics_Devices_And_Circuits/chapter5.ipynb b/Electronics_Devices_And_Circuits/chapter5.ipynb
new file mode 100755
index 00000000..437b0a36
--- /dev/null
+++ b/Electronics_Devices_And_Circuits/chapter5.ipynb
@@ -0,0 +1,653 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:9eef90d3b867f35b7e7b7ae71f5d96e96e47a495dc677c7492d34992d7905497"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "Chapter 5:Large Signals Amplifiers"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 5.1,Page number 280"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Rb=1*10**3                    #base resistance(ohms)\n",
+      "Vcc=20                        #supply voltage(V)\n",
+      "Rc=20                         #collector resistance(ohms) \n",
+      "beeta=25                      #current gain \n",
+      "Vbe=0.7                       #base to emitter voltage(V) \n",
+      "ib=10*10**-3                  #base current(ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "Ibq=(Vcc-Vbe)/Rb               #current(A)\n",
+      "Icq=beeta*Ibq                  #current(A)\n",
+      "Vceq=Vcc-(Icq*Rc)              #collector voltage(V)\n",
+      "ic=beeta*ib                    #collector current(A)\n",
+      "Po=((ic/(math.sqrt(2)))**2)*Rc #output voltage(V)\n",
+      "Pi=Vcc*Icq                     #input power(W)\n",
+      "eta=(Po/Pi)*100                #efficiency     \n",
+      "Pd=Pi-((Icq**2)*Rc)-Po         #power dissipated(W)   \n",
+      "\n",
+      "#Results\n",
+      "print\"input power is Pi\",Pi,\"W\"\n",
+      "print\"output power is Po\",Po,\"W\"\n",
+      "print\"power dissipated is\",round(Pd,1),\"W\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "input power is Pi 9.65 W\n",
+        "output power is Po 0.625 W\n",
+        "power dissipated is 4.4 W\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 5.2,Page number 283"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration \n",
+      "Rl=500                           #load resistance(ohms)\n",
+      "Vceq=50                          #queinscent collector voltage(V)\n",
+      "beetamin=30                      #current gain minimum(at Q)\n",
+      "Icq=0.4                          #queinscent collector current(A)\n",
+      "Ibq=8                            #queinscent base current(mA)\n",
+      "\n",
+      "#Calculations\n",
+      "Rac=Vceq/Icq                       #ac resistance(ohms)\n",
+      "beeta=(Icq*10**-3)/Ibq             #current gain\n",
+      "Re=5/Icq                           #emitter resistance(ohms)\n",
+      "Rc=(512.5*Rac)/(512.5-Rac)         #as Re+Rl=500+12.5=512.5\n",
+      "Vcc=5+Vceq+(Icq*Rc)                #supply voltage(V)   \n",
+      "Rb=(beetamin*Re)/10                #base resistance(ohms)\n",
+      "R1=39.5                            #solving 125=Rc||(Rl+Re) and Vbb=Vcc*(R1/(R1+R2))\n",
+      "R2=750\n",
+      "Pi=120*Icq                         #Vcc chosen as 120\n",
+      "r=(Rc*Rl)/(Rc+Rl)\n",
+      "Poac=(100/(2*math.sqrt(2)))**2/r  #output power(W)\n",
+      "etamax=Poac/Pi                    #efficiency\n",
+      "Poac1=(100/(2*math.sqrt(2)))**2/Rl #ac power absorbed by load(W)\n",
+      "eta=Poac1/Pi   \n",
+      "Pc=(Icq**2)*Rc                  #power lost in Rc(W)\n",
+      "Pe=(Icq**2)*Re                  #power lost in Re(W)\n",
+      "Pd=Pi-Pc-Pe-Poac                  #power consumed(W)\n",
+      "\n",
+      "#Results\n",
+      "print\"input power is Pi\",Pi,\"W\"\n",
+      "print\"output power is Po\",round(Poac,2),\"W\"\n",
+      "print\"dissipated power is\",round(Pd,2),\"W\"\n",
+      "print\"values of R1,R2,Re and Rc are\",R1,\"ohms,\",R2,\"ohms,\",Re,\"ohms and\",round(Rc),\"ohms resp. (Calculated value of Rc is wrong in the book)\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "input power is Pi 48.0 W\n",
+        "output power is Po 10.06 W\n",
+        "dissipated power is 9.49 W\n",
+        "values of R1,R2,Re and Rc are 39.5 ohms, 750 ohms, 12.5 ohms and 165.0 ohms resp. (Calculated value of Rc is wrong in the book)\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 5.3,Page number 285"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Pmax=10                         #power maximum(W)\n",
+      "Ic=1                            #collector current(A)\n",
+      "Vcemax=100                      #max collector to emitter current(V)\n",
+      "Vcemin=2                        #min collector to emitter current(V)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Vceq=46                       #Vce at Q point             \n",
+      "Icq=0.21                      #Ic  at Q point             \n",
+      "Vcc=92                        #supply voltage(V)\n",
+      "ic=0.42                       #collector current(A) \n",
+      "\n",
+      "#Part b\n",
+      "Rl=Vceq/Icq                       #load resistance(ohms)\n",
+      "\n",
+      "#Part c\n",
+      "Pi=Vcc*Icq                        #input power(W)\n",
+      "Po=((ic/(2*math.sqrt(2)))**2)*Rl  #output power(W)\n",
+      "eta=(Po/Pi)*100                   #efficiency\n",
+      "\n",
+      "#Results\n",
+      "print\"Rl for maximum power input is\",round(Rl),\"ohms\"\n",
+      "print\"input power is is\",Pi,\"W\"\n",
+      "print\"Po is\",Po\n",
+      "print\"eta is\",eta,\"%\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Rl for maximum power input is 219.0 ohms\n",
+        "input power is is 19.32 W\n",
+        "Po is 4.83\n",
+        "eta is 25.0 %\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 5.4,Page number 286"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Vcc=15                   #supply voltage(V)\n",
+      "beeta=40.                #current gain\n",
+      "Icq=5.                   #Ic at Q(mA)\n",
+      "Vceq=7.5                 #Vce at Q(V)      \n",
+      "icswing=10               #swing in ic(mA) \n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Rl=Vceq/Icq*10**-3       #load resistance(ohms)    \n",
+      "\n",
+      "#Part b\n",
+      "Ibq=Icq/beeta            #base current at Q(uA)\n",
+      "\n",
+      "#Part c\n",
+      "ibswing=icswing/beeta                   #swing in ib(mA)\n",
+      "Pac=Rl*(icswing/(2*math.sqrt(2)))**2    #ac power(W)\n",
+      "Pdc=Vcc*(Icq*10**-3)                    #dc power(W)\n",
+      "eta=(Pac/Pdc)*100                       #efficiency\n",
+      "\n",
+      "#Results\n",
+      "print\"a)value of Rl is\",round(Rl/1E-6),\"ohms\"\n",
+      "print\"b)Ibq is\",round(Ibq/1E-3),\"uA\"\n",
+      "print\"c)ac power output is\",round((Pac/1E-3),2),\"mW\"\n",
+      "print\"efficiency is\",eta,\"%\"\n",
+      "print\"corresponding swing in ib is\",ibswing,\"mA\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)value of Rl is 1500.0 ohms\n",
+        "b)Ibq is 125.0 uA\n",
+        "c)ac power output is 18.75 mW\n",
+        "efficiency is 25.0 %\n",
+        "corresponding swing in ib is 0.25 mA\n"
+       ]
+      }
+     ],
+     "prompt_number": 24
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 5.5,Page number 288"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Vcc=Vce=10                  #supply voltage(V)  \n",
+      "Icq=140*10**-3              #Ic at Q point(A)\n",
+      "Rl=8                        #load resistance(ohms)\n",
+      "vce=16                      #instantaneous collector to emitter voltage(V)\n",
+      "ic=235*10**-3               #instantaneous collector current(A)\n",
+      "\n",
+      "#Calculations\n",
+      "RL=Vcc/Icq\n",
+      "r=math.sqrt(RL/Rl)                             #load resistance for max ac swing(ohms)\n",
+      "Po=(vce*ic)/(2*math.sqrt(2)*2*math.sqrt(2))    #output power(W)\n",
+      "Pi=Vcc*Icq                                     #input power(W)   \n",
+      "eta=Po/Pi                                      #efficiency\n",
+      "Pd=Pi-Po                                       #dissipated power(W)  \n",
+      "\n",
+      "#Results\n",
+      "print\"a)transformation ratio is\",round(r)\n",
+      "print\"c)power output is\",Po,\"W\"\n",
+      "print\"efficiency is\",round(eta*100,2),\"%\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)transformation ratio is 3.0\n",
+        "c)power output is 0.47 W\n",
+        "efficiency is 33.57 %\n"
+       ]
+      }
+     ],
+     "prompt_number": 5
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 5.6,Page number 290"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Rl=4.5                    #load resistance(ohms)\n",
+      "Vceq=50                   #Vc at point Q(V)\n",
+      "Icq=400*10**-3            #Ic at Q(A)\n",
+      "Re=12.5                   #emitter resistance(ohms)\n",
+      "Vcemax=90                 #from figure \n",
+      "Vcemin=10                 #from figure\n",
+      "Icmax=730                 #max Ic(mA)\n",
+      "Icmin=30                  #min Ic(mA)   \n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Rac=Vceq/Icq                #ac resistance(ohms)\n",
+      "n=math.sqrt(Rac/Rl)         #as n=N1/N2 and Rac=(N1/N2)^2*Rl\n",
+      "\n",
+      "#Part b\n",
+      "Vcc=Vceq+(Icq*Re)           #supply voltage(V)   \n",
+      "\n",
+      "#Part c\n",
+      "vce=Vcemax-Vcemin                                    #instantaneous collector to emitter voltage(V)\n",
+      "ic=Icmax-Icmin                                       #instantaneous collector current(mA)\n",
+      "Po=(vce*ic)/((2*math.sqrt(2))*(2*math.sqrt(2)))      #output voltage(V)\n",
+      "Pi=Vcc*Icq                                           #input voltage(V)  \n",
+      "eta=(Po/Pi)*100                                      #efficiency\n",
+      "Pd=Pi-(Icq**2*Re)-Po*10**-3                          #dissipated power(W)\n",
+      "\n",
+      "#Results\n",
+      "print\"a)transformation ratio is\",round(n,2)\n",
+      "print\"b)Vcc is\",Vcc,\"V\"\n",
+      "print\"c)power efficiency for the load is\",round((eta/1E+3),1),\"%\"\n",
+      "print\"power dissipated is\",Pd,\"W\"\n"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)transformation ratio is 5.27\n",
+        "b)Vcc is 55.0 V\n",
+        "c)power efficiency for the load is 31.8 %\n",
+        "power dissipated is 13.0 W\n"
+       ]
+      }
+     ],
+     "prompt_number": 36
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 5.7,Page number 295"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Finding input power,output power,Pd,efficiency,\n",
+      "\n",
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Vcc=30                        #supply voltage(V)\n",
+      "Rl=16                         #load resistance(ohms)    \n",
+      "n=2                           #transformation ratio\n",
+      "Im=1                          #peak value of current(A)\n",
+      "etamax=78.54                  #max efficiency(%)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Rl1=Rl*(n/2)**2                  #load resistance(ohms)\n",
+      "Pi=(2*Vcc*Im)/math.pi            #input power(W)\n",
+      "Pimax=(2*Vcc**2)/((math.pi)*Rl1) #input power max(W)\n",
+      "\n",
+      "#Part b\n",
+      "Po=((Im**2)*Rl1)/2               #output power(W)\n",
+      "Pomax=(Vcc**2)/(2*Rl1)           #output power max(W)\n",
+      "\n",
+      "#Part c\n",
+      "eta=Po/Pi                        #efficiency\n",
+      "                \n",
+      "\n",
+      "#Part d\n",
+      "P=((2*Vcc*Im)/math.pi)-((Im**2*Rl1)/2) #Power dissipated by transistors(W)\n",
+      "Pd=P/2                                 #power dissipated by each transistors\n",
+      "Pmax=(2*Vcc**2)/((math.pi)**2*Rl1)     #max power dissipated by transistors\n",
+      "Pdmax=Pmax/2                           #max power dissipated by each transistor\n",
+      "\n",
+      "#Results\n",
+      "print\"a)input power is\",round(Pi,1),\"W and  max input power is\",round(Pimax,2),\"W\"\n",
+      "print\"b)output power \",Po,\"W and max output power is\",round(Pomax,2),\"W\"\n",
+      "print\"c)power efficiency for the load is\",round((eta/1E-2),2),\"% and its max value is\",etamax,\"%\"\n",
+      "print\"power dissipated by each transiator is\",round(Pd,1),\"W and  max value is\",round(Pdmax,1),\"W\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)input power is 19.1 W and  max input power is 35.81 W\n",
+        "b)output power  8 W and max output power is 28.0 W\n",
+        "c)power efficiency for the load is 41.89 % and its max value is 78.54 %\n",
+        "power dissipated by each transiator is 5.5 W and  max value is 5.7 W\n"
+       ]
+      }
+     ],
+     "prompt_number": 5
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 5.8,Page number 296"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "#Variable declaration\n",
+      "Pd=10\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Poacmax=10.                #as Pd=Po(ac)max by class A\n",
+      "\n",
+      "#Part b\n",
+      "Pd=2*Poacmax               #power dissipated(W)\n",
+      "Poacmax1=146/2             #max output power by class B\n",
+      "f=Poacmax1/Poacmax         #factor by which power of class B is greater than class A\n",
+      "                \n",
+      "#Results\n",
+      "print\"maximum signal output powerclass A produce is\",Poacmax,\"W\"\n",
+      "print\"maximum signal output powerclass  produce is\",Poacmax1,\"W\"\n",
+      "print\"factor by which power in class b is larger than power in class A transformer is\",f"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "maximum signal output powerclass A produce is 10.0 W\n",
+        "maximum signal output powerclass  produce is 73 W\n",
+        "factor by which power in class b is larger than power in class A transformer is 7.3\n"
+       ]
+      }
+     ],
+     "prompt_number": 14
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 5.9,Page number 300"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Vcc=30.                          #supply voltage(V)\n",
+      "Im=1                             #peak value of current(A)\n",
+      "Rl=10.                           #load resistance(ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Pi=(Vcc*Im)/math.pi             #input power(W)\n",
+      "Pimax=(Vcc**2)/(math.pi*2*Rl)   #max input power(W)\n",
+      "\n",
+      "#Part b\n",
+      "Po=((Im**2)*Rl)/2               #output power(W)\n",
+      "Pomax=(Vcc**2)/(8*Rl)           #output power max(W)\n",
+      "\n",
+      "#Part c\n",
+      "eta=Po/Pi                     #efficiency\n",
+      "etamax=Pomax/Pimax            #efficiency max                \n",
+      "\n",
+      "#Part d\n",
+      "Pd=Pi-Po                             #Power dissipated by transistors(W)                            \n",
+      "Pmax=(Vcc**2)/(2*(math.pi)**2*Rl)    #max power dissipated by transistors\n",
+      "                              \n",
+      "#Results\n",
+      "print\"a)input power is \",round(Pi,2),\"W and max input power is\",round(Pimax,2),\"W\"\n",
+      "print\"b)output power is \",Po,\"W and max output power is\",round(Pomax,2),\"W\"\n",
+      "print\"c)power efficiency for the load is\",round((eta/1E-2),2),\"% and its max value is\",round((etamax/1E-2),2),\"%\"\n",
+      "print\"power dissipated and its max value are\",round(Pd,2),\"W and\",round(Pmax,2),\"W\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)input power is  9.55 W and max input power is 14.32 W\n",
+        "b)output power is  5.0 W and max output power is 11.25 W\n",
+        "c)power efficiency for the load is 52.36 % and its max value is 78.54 %\n",
+        "power dissipated and its max value are 4.55 W and 4.56 W\n"
+       ]
+      }
+     ],
+     "prompt_number": 8
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 5.10,Page number 303"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "P1=2                          #transistor power(W)\n",
+      "Rl=5*10**3.                   #load resistance()\n",
+      "Ic=35                         #collector current(mA)   \n",
+      "\n",
+      "#Calculations\n",
+      "Bo=40-Ic                           \n",
+      "B1=math.sqrt((2*P1)/Rl)\n",
+      "B2=Bo\n",
+      "D2=(B2/B1)*100                #second harmonic distortion(%)\n",
+      "\n",
+      "#Results\n",
+      "print\"second harmonic distortion is\",round((D2/1E+3),2),\"%\"\n"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "second harmonic distortion is 17.68 %\n"
+       ]
+      }
+     ],
+     "prompt_number": 7
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 5.12,Page number 314"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "Vcc=15.                            #supply voltage(V)\n",
+      "Rl=10.                             #load resistance(ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "Immax=Vcc/Rl                      #max peak current(A)\n",
+      "Irmsmax=Immax/(math.sqrt(2))      #max rms current(A)\n",
+      "Pomax=Irmsmax**2*Rl               #max output power(W)\n",
+      "Pi=(2*Vcc*Immax)/math.pi          #max input power(W)\n",
+      "eta=Pomax/Pi                      #efficiency\n",
+      "\n",
+      "#Part b \n",
+      "Im=(2*Vcc)/(math.pi*Rl)                       #peak current(A)\n",
+      "Pdmax=((2*Vcc*Im)/(math.pi))-((Im**2*Rl)/2)   #max power dissipated(W)\n",
+      "eta1=((Im**2)*Rl*math.pi)/(2*2*Vcc*Im)        #efficiency\n",
+      "\n",
+      "#Results\n",
+      "print\"a)max signal output power,collector dissipation  are\",Pomax,\"W,\",round(Pi,2),\"W and efficiency is\",round((eta/1E-2),2),\"%\"\n",
+      "print\"b)max dissipation of each transistor and corresponding efficiency is\",round(Pdmax,2),\"W and\",eta1,\"resp.\"\n"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)max signal output power,collector dissipation  are 11.25 W, 14.32 W and efficiency is 78.54 %\n",
+        "b)max dissipation of each transistor and corresponding efficiency is 4.56 W and 0.5 resp.\n"
+       ]
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 5.13,Page number 315"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Calculations\n",
+      "eta=0.5              #As Po(ac)=Vcc^2/2*pi^2*Rl and Pi(dc)=Vcc^2/pi^2*Rl\n",
+      "                     #put these in eta=Po(ac)/Pi(dc) which is 1/2=0.5  \n",
+      "    \n",
+      "#Results\n",
+      "print\"push pull amplifier efficiency is\",round(eta/1E-2),\"%\"\n"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "push pull amplifier efficiency is 50.0 %\n"
+       ]
+      }
+     ],
+     "prompt_number": 27
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Electronics_Devices_And_Circuits/chapter7.ipynb b/Electronics_Devices_And_Circuits/chapter7.ipynb
new file mode 100755
index 00000000..f37b3943
--- /dev/null
+++ b/Electronics_Devices_And_Circuits/chapter7.ipynb
@@ -0,0 +1,645 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:4a9283ba6472e11de214bfc0c69a7f007685d94fb7b513179011a2e471e81b7b"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "Chapter 7:Operational Amplifiers"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 7.1,Page number 361"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "V1=120                   #negative terminal Vn(uV)\n",
+      "V2=80                    #positive terminal Vp(uV)\n",
+      "Ad=10**3                 #difference mode gain\n",
+      "\n",
+      "\n",
+      "#Calculations\n",
+      "Vd=V1-V2                #difference mode signal(uV)  \n",
+      "Vc=(V1+V2)/2            #common mode signal(uV)\n",
+      "\n",
+      "#Part a\n",
+      "CMRR=100.                    #common mode rejection ratio\n",
+      "Vo=Ad*Vd*(1+(Vc/(CMRR*Vd)))  #output voltage(mV)\n",
+      "          \n",
+      "#Part b\n",
+      "CMRR=10**5.                    #common mode rejection ratio\n",
+      "Vo1=Ad*Vd*(1+(1/CMRR)*(Vc/Vd)) #output voltage(mV) \n",
+      "\n",
+      "#Results\n",
+      "print\"output voltage is\",round(Vo/1E+3),\"mV\"\n",
+      "print\"output voltage is\",round(Vo1/1E+3),\"mV\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "output voltage is 41.0 mV\n",
+        "output voltage is 40.0 mV\n"
+       ]
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 7.2,Page number 365"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "deltavi=0.5             #change in vi(V)\n",
+      "deltat=10               #change in time(us)\n",
+      "s=1                     #slew rate(V/us)\n",
+      "\n",
+      "#Calculations\n",
+      "Kvf=(s*deltat)/deltavi  #closed loop gain of amplifier\n",
+      "\n",
+      "#Results\n",
+      "print\"closed loop gain of amplifier is\",Kvf"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "closed loop gain of amplifier is 20.0\n"
+       ]
+      }
+     ],
+     "prompt_number": 10
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 7.3,Page number 365"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "f=50*10**3.                  #OPAMP freequency(Hz)\n",
+      "Vm=0.02                      #maximum value of signal voltage(V)\n",
+      "S=.5*10**6                     #slew rate(V/s)\n",
+      "\n",
+      "#Calculations\n",
+      "Kvf=S/(2*(math.pi)*f*Vm)    #closed loop gain of amplifier\n",
+      "\n",
+      "#Results\n",
+      "print\"closed loop gain of amplifier is\",round(Kvf)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "closed loop gain of amplifier is 80.0\n"
+       ]
+      }
+     ],
+     "prompt_number": 18
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 7.4,Page number 369"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Ic=100              #current at quinscent point(uA)\n",
+      "beta=2000.          #current gain\n",
+      "Ad=250              #difference mode gain\n",
+      "CMRR=5000           #as 74 dB=5000,common mode rejection ratio(dB)\n",
+      "\n",
+      "#Calculations\n",
+      "rpi=(25*beta)/Ic     #dynamic internal resistance(k ohms)  \n",
+      "gm=beta/rpi          #transconductance(mS)\n",
+      "Re=CMRR/gm           #emitter resistance(k ohms)\n",
+      "Rc=(Ad*2)/gm         #collector resistance(k ohms) from formula Ad=gmRc/2\n",
+      "Rin=2*rpi            #input resistance(k ohms)\n",
+      "\n",
+      "#Results\n",
+      "print\"Re is\",Re,\"k ohms\"\n",
+      "print\"Rc is\",Rc,\"k ohms\"\n",
+      "print\"input resistance is\",Rin,\"k ohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Re is 1250.0 k ohms\n",
+        "Rc is 125.0 k ohms\n",
+        "input resistance is 1000.0 k ohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 7.6,Page number 371"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Icq=.428            #current at quinscent point(uA)\n",
+      "beta=200.           #current gain\n",
+      "                    #as 74 dB=5000,common mode rejection ratio(dB)\n",
+      "Rc=10.              #collector resistance(k ohms)    \n",
+      "Re=16.              #emitter resistance(k ohms)   \n",
+      "Vcc=15.             #supply voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part b\n",
+      "Ibq=Icq/beta         #Ib at Q(uA)\n",
+      "rpi=(25*beta)/Icq    #dynamic resistance(k ohms)\n",
+      "gm=beta/rpi          #transconductance\n",
+      "\n",
+      "#Part b\n",
+      "vo1=Vcc-(Icq*Rc)    #terminal 1 voltage(V) \n",
+      "vo2=vo1             #terminal 2 voltage(V) \n",
+      "\n",
+      "#Part c                  \n",
+      "Ad=(gm*Rc)/2        #differential mode gain\n",
+      "Ac=Rc/(2*Re)        #common mode gain\n",
+      "CMRR=Ad/Ac          #common mode rejection ratio\n",
+      "\n",
+      "#Part d\n",
+      "Rid=2*rpi                     #differential input resistance(k ohms)\n",
+      "rpi=11.7                      #dynamic resistance(k ohms)\n",
+      "Ric=rpi+(2*(beta+1)*Re)       #common mode input resistance(k ohms)\n",
+      "\n",
+      "#Results\n",
+      "print\"Icq is\",Icq,\"mA,and Ibq is \",round((Ibq/1E-3),2),\"uA\"\n",
+      "print\"vo1 and vo2 have same value as\",vo1,\"V\"\n",
+      "print\"\",\n",
+      "print\"Ad:\",round(Ad/1E-3),\",Ac:\",round(Ac,3),\"and CMRR is\",round(CMRR/1E-3)\n",
+      "print\"Rid is\",round((Rid/1E+3),1),\"K ohms and Ric is\",round((Ric/1E+3),2),\" Mohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Icq is 0.428 mA,and Ibq is  2.14 uA\n",
+        "vo1 and vo2 have same value as 10.72 V\n",
+        " Ad: 86.0 ,Ac: 0.313 and CMRR is 274.0\n",
+        "Rid is 23.4 K ohms and Ric is 6.44  Mohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 7.7,Page number 373"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "R1=10.                   #series resistance(K ohms)\n",
+      "Rf=10**3.                #feedback resistance(k ohms)   \n",
+      "vo=-5.                   #output voltage(V)\n",
+      "Ri=1000                  #input resistance(k ohms)\n",
+      "Av=2.5*10**5             #gain\n",
+      "\n",
+      "#Calculations\n",
+      "v1=-vo*(R1/Rf)           #input signal voltage(V)\n",
+      "vi=-vo/Av                #inverting voltage(V)  \n",
+      "i1=((v1*10**-3)-vi)/R1   #current through R1(uA)\n",
+      "ii=vi/Ri                 #inverting current(uA)\n",
+      "iF=-ii                   #forward current(uA)\n",
+      "\n",
+      "#Results\n",
+      "print\"value of vi is\",vi,\"mV\"\n",
+      "print\"value of ii:\",ii,\"uA i1:,\",i1,\"uA and iF is\",iF,\"uA\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "value of vi is 2e-05 mV\n",
+        "value of ii: 2e-08 uA i1:, 3e-06 uA and iF is -2e-08 uA\n"
+       ]
+      }
+     ],
+     "prompt_number": 5
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 7.8,Page number 374"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vs=4                    #source voltage(V)\n",
+      "R1=10.                   #resistance(k ohms)\n",
+      "Vb=Va=2                 #voltage at point A and point B\n",
+      "Rf=30                   #forward resistance(k ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "I=(Vs-Vb)/R1           #current(mA)\n",
+      "Vo=(-I*Rf)+Vb          #output voltage(V)  \n",
+      "\n",
+      "#Result\n",
+      "print\"output voltage\",Vo,\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "output voltage -4.0 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 45
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 7.9,Page number 375"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Rf=2              #as vs=2sinwt and vo=(1+Rf/Rs)*vb and vB=vA=vs\n",
+      "Rs=1\n",
+      "\n",
+      "\n",
+      "#Calculations\n",
+      "vo=(1+(Rf/Rs))*2       #output voltage(V)\n",
+      "\n",
+      "#Result\n",
+      "print\"output voltage\",vo,\"sinwt\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "output voltage 6 sinwt\n"
+       ]
+      }
+     ],
+     "prompt_number": 50
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 7.10,Page number 377"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Ro=100.                 #output resistance(ohms)\n",
+      "vo=10.                  #output voltage(V)\n",
+      "A=10**5.                #gain \n",
+      "Ri=100*10**3            #input resistance(ohms) \n",
+      "Rs=1*10**3.             #resistance(ohms)\n",
+      "Rl=10*10**3             #load resistance(ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part i\n",
+      "iL=vo/Rl                  #load current(mA)\n",
+      "Avi=vo+(iL*Ro)            #voltage gain without feedback\n",
+      "vi=Avi/A                  #voltage(V)\n",
+      "ii=vi/Ri                  #current(A)  \n",
+      "vs=vo+ii*(Rs+Ri)          #source voltage(V)\n",
+      "\n",
+      "#Part ii\n",
+      "Avf=vo/vs                #voltage gain with feedback  \n",
+      "\n",
+      "\n",
+      "#Part iii\n",
+      "Rif=vs/ii              #input resistance(ohms) \n",
+      "Rof=Ro/A               #output resistance(ohms)\n",
+      "\n",
+      "#Results\n",
+      "print\"vs is\",round(vs,4),\"V\"\n",
+      "print\"vo/vs that is Avf is\",Avf\n",
+      "print\"input and output resistances are\",Rif,Rof,\"ohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "vs is 10.0001 V\n",
+        "vo/vs that is Avf is 0.999989799104\n",
+        "input and output resistances are 9901091099.01 0.001 ohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 6
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 7.11,Page number 382"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vb=Va=3                     #voltage at A and B \n",
+      "R1=40*10**3.                #input resistance(ohms)\n",
+      "t=50*10**-3                 #time after switch is open(mS)\n",
+      "V1=5                        #input voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "vo=-3                       #as Va=Vb=3\n",
+      "\n",
+      "#Part b\n",
+      "i1=(V1-Vb)/R1               #input current(A)\n",
+      "vo1=(-250*t)-Va             #vo at 50 mS\n",
+      "\n",
+      "#Result\n",
+      "print\"output voltage\",vo1,\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "output voltage -15.5 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 6
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 7.14,Page number 388"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "BW=30*10**3               #specified bandwidth(k Hz)\n",
+      "fc=18*10**3               #centered frequency(Hz)\n",
+      "R1=20                     #resistance(k ohms) \n",
+      "R2=180                    #resistance(k ohms)  \n",
+      "C=1.2*10**-9              #capacitance(F)\n",
+      "G=40                      #pass band gain(dB)\n",
+      "g=20                      #pass region gain(dB)\n",
+      "\n",
+      "#Calculationsv\n",
+      "fc1=fc-(BW/2)             #high pass section frequency(Hz)\n",
+      "fc2=fc+(BW/2)             #low pass section frequency(Hz)\n",
+      "Rfc1=1/(2*math.pi*fc1*C)  #high pass section resistance(k ohms)\n",
+      "Rfc2=1/(2*math.pi*fc2*C)  #low pass section resistance(k ohms)\n",
+      "Gfc1=G-g                  #gain at frequency 0.3KHz(dB)\n",
+      "Gfc2=G-2*6                #gain at frequency 132KHz(dB)\n",
+      "\n",
+      "#Results\n",
+      "print\"R1 and R2 are\",R1,\"K ohms and\",R2,\"K ohms\"\n",
+      "print\"Rfc1 is\",round(Rfc1/1E+3),\"k ohms and Rfc2 is\",round(Rfc2/1E+3),\"k ohms\"\n",
+      "print\"filter gain at frequencies 0.3 KHz is\",Gfc1,\"dB and 132 k Hz are\",Gfc2,\"dB\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "R1 and R2 are 20 K ohms and 180 K ohms\n",
+        "Rfc1 is 44.0 k ohms and Rfc2 is 4.0 k ohms\n",
+        "filter gain at frequencies 0.3 KHz is 20 dB and 132 k Hz are 28 dB\n"
+       ]
+      }
+     ],
+     "prompt_number": 7
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 7.21,Page number 402"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "R=250            #resistance(k ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "#part a\n",
+      "R1=-R/(-5)    #as vo=-5va+3vb(given),so when vb=0,vo/voa=-250/R1=-5\n",
+      "\n",
+      "#part b\n",
+      "R2=R1/(2-1)   #as va=0\n",
+      "              #vx=(R1/R1+R)*vob=(1/6)*vb\n",
+      "              #vy=(R2/R1+R2)*vb\n",
+      "              #vx=vy\n",
+      "              #(1/6)*vob=(R2/R1+R2)*vb\n",
+      "              #vob=3vb\n",
+      "              #(1/6)*3=R2/(50+R2)\n",
+      "                \n",
+      "#Result\n",
+      "print\"R1 and R2 are\",R1,\"K ohms and\",R2,\"K ohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "R1 and R2 are 50 K ohms and 50 K ohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 11
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 7.22,Page number 403"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "R1=10*10**3                       #resistance(k ohms)\n",
+      "C1=10**-6                         #capacitance(uF) \n",
+      "C=0.1*10**-6                      #capacitance(uF) \n",
+      "R=100*10**3                       #resistance(k ohms)   \n",
+      "\n",
+      "#Calculations\n",
+      "#part b \n",
+      "wc1=1/C1*R1                     #angular frequency(rad/s)\n",
+      "wc2=1/C*R                       #angular frequency(rad/s)\n",
+      "wc=wc1=wc2                      #angular frequency(rad/s)\n",
+      "\n",
+      "#Results\n",
+      "print\"wc1 is\",wc1/1E+10,\"rad/s\"\n",
+      "print\"wc2 is\",wc2/1e+10,\"rad/s\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "wc1 is 100.0 rad/s\n",
+        "wc2 is 100.0 rad/s\n"
+       ]
+      }
+     ],
+     "prompt_number": 15
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 7.23,Page number 404"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "vo1=5                  #say (V)\n",
+      "K=25                   #proportionality constant  \n",
+      "Q=250                  #volume of fluid passed across metering point(cm^3) \n",
+      "R1=2.5                  #output resistance(k ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "C1=(K*Q)/(R1*vo1)     #capacitor(nF)\n",
+      "\n",
+      "#Results\n",
+      "print\"C1 is\",round(C1/1E+1),\"uF\"\n",
+      "print\"vo1 is -5V when Q=250 cm^3\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "C1 is 50.0 uF\n",
+        "vo1 is -5V when Q=250 cm^3\n"
+       ]
+      }
+     ],
+     "prompt_number": 6
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Electronics_Devices_And_Circuits/chapter8.ipynb b/Electronics_Devices_And_Circuits/chapter8.ipynb
new file mode 100755
index 00000000..326b2cab
--- /dev/null
+++ b/Electronics_Devices_And_Circuits/chapter8.ipynb
@@ -0,0 +1,435 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:7039c5014fcc7b7ac57b07f9ca218d5a9c1cf6429694e23e4e8bce3552a45c07"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "Chapter 8:Multivibrators And Switching Regulators"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 8.1,Page number 426"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "C=0.1                      #capacitance(uF)\n",
+      "R1=10                      #resistance(k ohms)\n",
+      "R2=2.3                     #resistance(k ohms)\n",
+      "Vcc=12.                    #supply voltage(V) \n",
+      "Rl=10**3.                  #resistance(k ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "f=1/(0.693*C*(R2+R1/2))    #frequency(Hz)\n",
+      "\n",
+      "#Part b\n",
+      "D=(1+(R2/R1))/(1+2*(R2/R1))*100          #duty cycle\n",
+      " \n",
+      "#Part c\n",
+      "#(i)\n",
+      "T1=0.693*C*(R1+R2)                        #time period through R1(ms)\n",
+      "T2=0.693*R2*C                             #time period through R2(ms)\n",
+      "Pavg=(Vcc/Rl)**2*(T1/(T1+T2))             #average power dissipated during current sourcing(mW)\n",
+      "\n",
+      "#Part d\n",
+      "Pavg1=(T2/(T1+T2))*(Vcc/Rl)**2           #average power dissipated during current sinking(mW)\n",
+      "\n",
+      "#Results\n",
+      "print\"print\",round(f,2),\"kHz\"\n",
+      "print\"duty cycle is\",round(D,2),\"%\"\n",
+      "print\"average power dissipated in current sourcing is\",round((Pavg/1E-3),3),\"mW\"\n",
+      "print\"average power dissipated in current sinking is\",round(Pavg1/1e-3,3),\"mW\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "print 1.98 kHz\n",
+        "duty cycle is 84.25 %\n",
+        "average power dissipated in current sourcing is 0.121 mW\n",
+        "average power dissipated in current sinking is 0.023 mW\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 8.2,Page number 426"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math \n",
+      "\n",
+      "#Variable declaration\n",
+      "t=1                               #time constant\n",
+      "e=1.8                             #e=R1/R2 min=1.8\n",
+      "e1=9.                              #e1=R1/R2 max=9\n",
+      "\n",
+      "#Calculations\n",
+      "Betamin=1/(1+e)                 #current gain minimum\n",
+      "Betamax=1/(1+e1)                #current gain maximum\n",
+      "Tmax=2*t*math.log((1+Betamin)/(1-Betamin))          \n",
+      "Tmin=2*t*math.log((1+Betamax)/(1-Betamax))                 \n",
+      "fmin=1/Tmax                     #minimum freq(Hz)\n",
+      "fmax=1/Tmin                     #maximum freq(k Hz)\n",
+      "\n",
+      "#Results\n",
+      "print\"fmin is\",round(fmin/1E-3),\"Hz and fmax is\",round(fmax,1),\"KHz\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "fmin is 669.0 Hz and fmax is 2.5 KHz\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 8.3,Page number 427"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "\n",
+      "#Variable declaration\n",
+      "C=0.01                     #capacitance(uF)\n",
+      "R2=15                      #resistance(k ohms)\n",
+      "Va2=4                      #voltage(V)\n",
+      "Vcc=15.                    #supply voltage(V)\n",
+      "R1=33                      #resistance(k ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "Va1=0.67*Vcc               #voltage(V)\n",
+      "Vamax=Va1+Va2              #Va maximum(V)\n",
+      "Vamin=Va1-Va2              #Va minimum(V)\n",
+      "T1max=C*(R1+R2)*(math.log((1-(Vamax/(2*Vcc)))/(1-(Vamax/Vcc))))   #time period(ms)\n",
+      "T1min=C*(R1+R2)*(math.log((1-(Vamin/(2*Vcc)))/(1-(Vamin/Vcc))))   #time period(ms)\n",
+      "T2=0.693*R2*C\n",
+      "fmax=1/(T1min+T2)                    #maximum frequency(K Hz)\n",
+      "fmin=1/(T1max+T2)                    #miniimum frequency(K Hz)\n",
+      "\n",
+      "#Results\n",
+      "print\"minimum freq is\",round(fmin,2),\"(solution given in the textbook is incorrect)\"\n",
+      "print\"maximum freq is\",round(fmax,2),\"(solution given in the textbook is incorrect)\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "minimum freq is 0.89 (solution given in the textbook is incorrect)\n",
+        "maximum freq is 4.1 (solution given in the textbook is incorrect)\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 8.4,Page number 433"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vi=25                         #input voltage(V) \n",
+      "Vsmax=30                      #supply voltage max(V)\n",
+      "Vomin=Vl=12                   #output minimum voltage or load voltage(V)\n",
+      "R1=20                         #load voltage(V)\n",
+      "Io=15.                        #output current(mA) \n",
+      "Iq=3.                         #quinscent current of regulator(mA)\n",
+      "Vo=20.                        #output voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "#(i)\n",
+      "Vimax=Vsmax                     #maximum permissible voltage(V)\n",
+      "Ro=0                            #for Vomin=beta=0\n",
+      "#(ii)\n",
+      "Vomax=Vi-2\n",
+      "betaVomax=Vomax-Vomin                   #output voltage(V)\n",
+      "R2max=(R1*betaVomax)/(Vomax-betaVomax)  #R2max(k ohms)\n",
+      "#(iii)\n",
+      "R3=betaVomax/Io                         #R3(k ohms)\n",
+      "\n",
+      "#Part b\n",
+      "Vt=(Iq*betaVomax)/Io                   #common terminal fall(V)\n",
+      "Vomin1=Vl+Vt                           #voltage output minimum(V)\n",
+      "\n",
+      "#Part c\n",
+      "betaVo=Vo-Vl                          #output voltage(V)\n",
+      "beta=betaVo/Vo                        #current gain\n",
+      "R2=(R1*betaVo)/(Vo-betaVo)            #R2(ohms)\n",
+      "\n",
+      "#Results\n",
+      "print\"a)i)max permissible supply voltage is\",Vimax,\"V\"\n",
+      "print\"ii)output voltage range for Vi=25V is\",Vomin,\"V to\",Vomax,\"V and R2max is\",R2max,\"k ohms\"\n",
+      "print\"iii)R3 is\",round(R3,2),\"kohms\"\n",
+      "print\"b)Vomin is\",Vomin1,\"V\"\n",
+      "print\"c)R2 is\",round(R2,2),\"ohms and R3 is\",round(R3,3),\"ohms\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "a)i)max permissible supply voltage is 30 V\n",
+        "ii)output voltage range for Vi=25V is 12 V to 23 V and R2max is 18 k ohms\n",
+        "iii)R3 is 0.73 kohms\n",
+        "b)Vomin is 14.2 V\n",
+        "c)R2 is 13.33 ohms and R3 is 0.733 ohms\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 8.5,Page number 434"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "A=.0025                     #voltage gain\n",
+      "Vi=8                        #input voltage(V)\n",
+      "R2=1.5                      #resistance 2(k ohms)\n",
+      "R1=1                        #resistance 1(k ohms)\n",
+      "Vl=5                        #load voltage(V)\n",
+      "\n",
+      "#Calculations\n",
+      "beta=R2/(R1+R2)               #current gain\n",
+      "Vo=Vl/(1-beta)                #output voltage(V)\n",
+      "Vo1=(A*Vi)/(1+(A*beta)-beta)  #output voltage ripple if Vi=8Vp-p\n",
+      "\n",
+      "#Results\n",
+      "print\"Vo is\",Vo,\"V\"\n",
+      "print\"expression of output voltage ripple\",round(Vo1,2),\"Vp-p\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Vo is 12.5 V\n",
+        "expression of output voltage ripple 0.05 Vp-p\n"
+       ]
+      }
+     ],
+     "prompt_number": 11
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 8.6,Page number 435"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Ro=7.5                               #output resistance(ohms)\n",
+      "hfe=50                          \n",
+      "Ve=20                                #voltage given to emitter(V)       \n",
+      "Vbe=0.8                              #base to emitter voltage(V)\n",
+      "Vc=15                                #collector voltage(V)\n",
+      "P=12                                 #maximum power dissipation(W)\n",
+      "Ib1=5                                #for minimum load current Il=0,Ib=5\n",
+      "\n",
+      "#Calculations\n",
+      "Io=(Vc/Ro)*10**3                      #output current(A)\n",
+      "Il=76                                 #load current(mA)\n",
+      "Is=Il+5                               #supply current(mA)\n",
+      "Ic=Io-Is                              #collector current(A)\n",
+      "Ib=Ic/hfe                             #base current(mA)\n",
+      "Ie=Ic-Ib                              #emitter current(mA)\n",
+      "Pt=(Ve*Ie)-(Vc*Ic)                    #power dissipated in transistor(W) \n",
+      "Pl=(Ve-Vbe)*Is-Vc*Il                   #power dissipated in LR\n",
+      "Vimax=(P+Vc*(Ic*10**-3))/(Ie*10**-3)  #input voltage maximum\n",
+      "Iomin=hfe*Ib1                         #output current minimum(mA)\n",
+      "\n",
+      "#Results\n",
+      "print\"power dissipated in the transistor is\",round((Pt/1E+3),2),\"W and in LR is\",round((Pl/1E+3),3),\"W\"\n",
+      "print\"maximum permissible input voltage is\",round(Vimax,2),\"V\"\n",
+      "print\"minimum load current for load voltage to remain stabalized is\",Iomin,\"mA\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "power dissipated in the transistor is 8.83 W and in LR is 0.415 W\n",
+        "maximum permissible input voltage is 21.69 V\n",
+        "minimum load current for load voltage to remain stabalized is 250 mA\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 8.7,Page number 440"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "VL=12            #load voltage(V)\n",
+      "I=2.             #current at 12 V\n",
+      "V=240            #dc source(V)\n",
+      "d=17/50.         #duty cycle\n",
+      "d1=0.6           #duty cycle\n",
+      "eta1=0.8         #efficiency\n",
+      "\n",
+      "#Calculations\n",
+      "P=VL*I                        #average load power(W)\n",
+      "Isav=(1*d)/2                  #average supply current(A)\n",
+      "Pav=V*Isav                    #average supply power(W)\n",
+      "eta=(P/Pav)*100               #regulator efficiency\n",
+      "Isav1=(1*d1)/2                #average supply current(A)\n",
+      "Il=(eta1*V*Isav1)/Vdc         #load current(A)\n",
+      "Po=Il*Vdc                     #power output(W)\n",
+      "\n",
+      "#Results\n",
+      "print\"regulator efficiency is\",round(eta,1),\"%\"\n",
+      "print\"average supply current is\",Il,\"A\"\n",
+      "print\"power output is\",Po,\"W\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "regulator efficiency is 58.8 %\n",
+        "average supply current is 4.8 A\n",
+        "power output is 57.6 W\n"
+       ]
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 8.8,Page number 441"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "Vs=200                #dc source voltage(V)\n",
+      "Il=5                  #current to load voltage(A)\n",
+      "Vl=15                 #load voltage(V)\n",
+      "eta=.85               #efficiency\n",
+      "f=20                  #oscillator frequency(Hz)\n",
+      "iSmax=2.6             #peak value of supply current(A)\n",
+      "P=100                 #full load power supply(W)\n",
+      "pdf=0.4               #pulse duty factor\n",
+      "\n",
+      "#Calculations\n",
+      "Isav=(Vl*Il)/(Vs*eta)   #average peak supply current(A)\n",
+      "iS=(2*Isav)/pdf         #supply current(A)\n",
+      "T=1000/f                #oscillation time period(uS)\n",
+      "tp=pdf*T                #transistor time(us)\n",
+      "d=iS/tp                 #change in iS with respect to time(A/us)\n",
+      "tp1=iSmax/d             #transistor time(us)\n",
+      "pdf1=tp1/T              #pulse duty factor\n",
+      "Isav1=(iSmax*pdf1)/2    #average peak supply current(A)\n",
+      "eta1=(P*100)/(Vs*Isav1) #efficiency\n",
+      "\n",
+      "#Results\n",
+      "print\"peak value of supply current is\",round(Isav,3),\"A\"\n",
+      "print\"pdf is\",round(pdf,3)\n",
+      "print\"overall efficienc is\",round(eta1,1),\"%\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "peak value of supply current is 0.441 A\n",
+        "pdf is 0.4\n",
+        "overall efficienc is 81.6 %\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Electronics_Devices_And_Circuits/chapter9.ipynb b/Electronics_Devices_And_Circuits/chapter9.ipynb
new file mode 100755
index 00000000..d1e5d34b
--- /dev/null
+++ b/Electronics_Devices_And_Circuits/chapter9.ipynb
@@ -0,0 +1,181 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:2422fd711b2fd56d40e4219a033361f9b209ac35916fbe15f9fd192288113f4c"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "Chapter 9:Integrated Circuit Fabrication"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 9.2,Page number 470"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "t=1                   #thickness(mil)         \n",
+      "e=1.6*10**-19         #charge on electron(C)\n",
+      "Pp=10**17             #concentration of phosphorous(atoms/cm^3)\n",
+      "Bn=5*10**16           #boron concentration(atoms/cm^3)\n",
+      "un=.135               #mobility(m^2/Vs)\n",
+      "\n",
+      "#Calculations\n",
+      "n=(Pp-Bn)*10**6       #net concentration(atoms/cm^3)\n",
+      "g=e*un*n              #conductivity()\n",
+      "rho=10**6/(g*25)      #resistivity(ohm mil)\n",
+      "Rs=rho/t              #sheet resistance(ohm mil^2)\n",
+      "\n",
+      "#Results\n",
+      "print\"Sheet resistance is\",round(Rs),\"ohm(mil**2)\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Sheet resistance is 37.0 ohm(mil**2)\n"
+       ]
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 9.3,Page number 471"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "R=20*10**3              #resistance of resistor(ohms)\n",
+      "w=25                    #width(um)\n",
+      "Rs=200                  #sheet resistance(ohm/square)\n",
+      "R1=5*10**3              #resistance(ohms)\n",
+      "\n",
+      "#Calculations\n",
+      "#Part a\n",
+      "l=(R*w)/Rs              #length required to fabricate 20 kohms(um)\n",
+      "\n",
+      "#Part b\n",
+      "L=25             #length of resistor of 5 k ohms(um)\n",
+      "w1=(Rs*L)/R1     #width required to fabricate 5 kohms(um)\n",
+      "#Results\n",
+      "print\"length required to fabricate 20 kohms resistor is\",l,\"um\"\n",
+      "print\"width required to fabricate 5 kohms resistor is\",w1,\"um\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "length required to fabricate 20 kohms resistor is 2500 um\n",
+        "width required to fabricate 5 kohms resistor is 1 um\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 9.4,Page number 471"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "C=0.4*10**-12               #capacitance(pF/um^2)\n",
+      "A=10**-12                   #area of film(m^2)\n",
+      "d=400*10**-10               #thickness of SiO2(amstrong)\n",
+      "Eo=8.849*10**-12            #absolute electrical permitivity of free space\n",
+      "\n",
+      "#Calculations\n",
+      "Er=(C*d)/(Eo*A)             #relative dielectric constant\n",
+      "\n",
+      "#Results\n",
+      "print\"relative dielectric constant of SiO2 is\",round(Er),\"(Solution given in the textbook is incorrect)\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "relative dielectric constant of SiO2 is 1808.0 (Solution given in the textbook is incorrect)\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example 9.5,Page number 471"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#Variable declaration\n",
+      "C=250*10**-12               #capacitance(pF)\n",
+      "d=500*10**-10               #thickness of SiO2 layer(amstrong)\n",
+      "Eo=8.849*10**-12            #absolute electrical permitivity of free space\n",
+      "Er=3.5                      #relative dielectric constant\n",
+      "\n",
+      "#Calculations\n",
+      "A=(C*d)/(Eo*Er)            #chip area(um^2)\n",
+      "\n",
+      "#Results\n",
+      "print\"chip area needed for a 250 pF  MOS capacitor\",round(A/1e-7,2),\"(um)^2(Solution given in the textbook is incorrect)\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "chip area needed for a 250 pF  MOS capacitor 4.04 (um)^2(Solution given in the textbook is incorrect)\n"
+       ]
+      }
+     ],
+     "prompt_number": 8
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
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