16 files changed, 3469 insertions, 0 deletions
diff --git a/Engineering_Physics_/Chapter1.ipynb b/Engineering_Physics_/Chapter1.ipynb
new file mode 100755
index 00000000..81c066a4
--- /dev/null
+++ b/Engineering_Physics_/Chapter1.ipynb
@@ -0,0 +1,69 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:b22f521510881a8fff0ac38eb4b560555d5bde9f0fb22681533a13e45849f4b7"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "1: Crystallography and Crystal imperfection"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 1.1, Page number 40"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "n=4;          #number of atoms per unit cell(FCC)\n",
+      "M=63.54;            #atomic weight of Cu(gm)\n",
+      "N=6.023*10**23;         #avagadro number(per g mole)\n",
+      "d111=2.08;       #interplanar spacing(angstrom)\n",
+      "h=1;\n",
+      "k=1;\n",
+      "l=1;\n",
+      "\n",
+      "#Calculation\n",
+      "d111=d111*10**-8;       #interplanar spacing(m)     \n",
+      "a=d111*math.sqrt((h**2)+(k**2)+(l**2));      \n",
+      "D=(n*M)/(N*(a**3));          #density of Cu(g/cc)\n",
+      "\n",
+      "#Result\n",
+      "print \"density of Cu metal is\",round(D,3),\"g/cc\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "density of Cu metal is 9.024 g/cc\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
+\ No newline at end of file
diff --git a/Engineering_Physics_/Chapter10.ipynb b/Engineering_Physics_/Chapter10.ipynb
new file mode 100755
index 00000000..f0870466
--- /dev/null
+++ b/Engineering_Physics_/Chapter10.ipynb
@@ -0,0 +1,306 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:38e4520c8655f11fdcb5696673580e95d36ab2ce43843aea287c93b1f1a0b257"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "10: Quantum Physics and Schrodinger wave equation"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 10.1, Page number 258"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "me=9.1*10**-31;   #mass of electron(kg)\n",
+      "h=6.625*10**-34;   #planck's constant(Jsec)\n",
+      "deltax=10**-8;    #uncertainity in position(m)\n",
+      "\n",
+      "#Calculation\n",
+      "deltap=(h/(2*math.pi*deltax));   #uncertainity principle(kgm/sec)\n",
+      "deltav=(deltap/me);   #minimum uncertainity in velocity(m/sec)\n",
+      "\n",
+      "#Result\n",
+      "print \"minimum uncertainity in velocity is\",round(deltav/10**5,3),\"*10**5 m/sec\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "minimum uncertainity in velocity is 0.116 *10**5 m/sec\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 10.2, Page number 259"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "lamda=0.2865*10**-10;   #wavelength(m)\n",
+      "mp=1.67*10**-27;   #mass of proton(kg)\n",
+      "h=6.625*10**-34;   #planck's constant(Jsec)\n",
+      "q=1.6*10**-19;     #charge of proton(C)\n",
+      "\n",
+      "#Calculation\n",
+      "v=(h/(mp*lamda));    #velocity(m/sec)\n",
+      "KE=0.5*mp*(v**2);    #kinetic energy of proton(J)\n",
+      "KE=KE/q;     #kinetic energy of proton(eV)\n",
+      "\n",
+      "#Result\n",
+      "print \"kinetic energy of proton is\",int(KE),\"eV\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "kinetic energy of proton is 1 eV\n"
+       ]
+      }
+     ],
+     "prompt_number": 5
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 10.3, Page number 259"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "KE=0.025;   #kinetic energy of neutron(eV)\n",
+      "q=1.6*10**-19;     #charge of proton(C)\n",
+      "mn=1.676*10**-27;  #mass of neutron(kg)\n",
+      "h=6.625*10**-34;   #planck's constant(Jsec)\n",
+      "me=9.1*10**-31;    #mass of electron(kg)\n",
+      "c=3*10**8;    #velocity of light(m/s)\n",
+      "\n",
+      "#Calculation\n",
+      "KE=KE*q;   #kinetic energy of neutron(J)\n",
+      "v=math.sqrt((2*KE)/mn);   #velocity(m/s)\n",
+      "lamdan=h/(mn*v);   #debroglie wavelength of neutron(m)\n",
+      "p=(h/lamdan);   #momentum of electron and photon(kgm/s)\n",
+      "ve=(p/me);   #velocity of electron(m/s)\n",
+      "Ee=0.5*p*ve;  #energy of electron(J)\n",
+      "Ee=Ee/q;    #energy of electron(eV)\n",
+      "Ep=h*c/lamdan;  #energy of photon(J)\n",
+      "Ep=Ep/q;       #energy of photon(eV)\n",
+      "\n",
+      "#Result\n",
+      "print \"wavelength of beam of neutron is\",round(lamdan*10**10,3),\"angstrom\"\n",
+      "print \"momentum of electron and photon is\",p,\"kgm/s\"\n",
+      "print \"energy of electron is\",round(Ee,2),\"eV\"\n",
+      "print \"energy of photon is\",round(Ep/10**3,2),\"*10**3 eV\"\n",
+      "print \"answers in the book vary due to rounding off errors\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "wavelength of beam of neutron is 1.809 angstrom\n",
+        "momentum of electron and photon is 3.66169359723e-24 kgm/s\n",
+        "energy of electron is 46.04 eV\n",
+        "energy of photon is 6.87 *10**3 eV\n",
+        "answers in the book vary due to rounding off errors\n"
+       ]
+      }
+     ],
+     "prompt_number": 10
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 10.4, Page number 260"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "e=1.6*10**-19;    #charge of electron(C)\n",
+      "V=200;    #potential difference(V)\n",
+      "lamda=0.0202*10**-10;   #debroglie wavelength(m)\n",
+      "h=6.625*10**-34;    #planck's constant(Jsec)\n",
+      "\n",
+      "#Calculation\n",
+      "#eV=0.5*m*(v^2)\n",
+      "#mv=sqrt(2*m*eV)\n",
+      "m=((h**2)/(2*(lamda**2)*e*V));    #mass of particle(kg)\n",
+      "\n",
+      "#Result\n",
+      "print \"mass of particle is\",m,\"kg\"\n",
+      "print \"hence it is a proton\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "mass of particle is 1.68069555834e-27 kg\n",
+        "hence it is a proton\n"
+       ]
+      }
+     ],
+     "prompt_number": 11
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 10.5, Page number 260"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration \n",
+      "mn=1.676*10**-27;   #mass of neutron(kg)\n",
+      "e=1.6*10**-19;    #charge of electron(C)\n",
+      "h=6.622*10**-34;   #planck's constant(Jsec)\n",
+      "\n",
+      "#Calculation\n",
+      "E=e;     #energy of neutron(J)\n",
+      "v=math.sqrt((2*E)/mn);   #velocity of neutron(m/sec)\n",
+      "lamda=(h/(mn*v));   #de-broglie wavelength(m)\n",
+      "\n",
+      "#Result\n",
+      "print \"de-broglie wavelength of neutron is\",round(lamda*10**10,3),\"angstrom\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "de-broglie wavelength of neutron is 0.286 angstrom\n"
+       ]
+      }
+     ],
+     "prompt_number": 15
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 10.6, Page number 261"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration \n",
+      "r=10**-14;    #radius(m)\n",
+      "h=6.625*10**-34;    #planck's constant(Jsec)\n",
+      "c=3*10**8;    #velocity of light(m/s)\n",
+      "mo=9.1*10**-31;   #rest mass of particle(kg)\n",
+      "q=1.6*10**-19;   #charge of electron(C)\n",
+      "\n",
+      "\n",
+      "#Calculation\n",
+      "#acc. to uncertainity principle delx*delp >= (h/2*%pi)\n",
+      "deltax=2*r;   #uncertainity in position(m)\n",
+      "deltap=(h/(2*math.pi*deltax));    ##uncertainity in momentum\n",
+      "#from einstein's relavistic relation E=mc2=KE+rest mass energy=0.5mv2+moc2\n",
+      "#when velocity of particle is very high\n",
+      "#m=(mo/sqrt(1-((v/c)^2))) where m-mass of particle with velocity v,mo-rest mass of particle, c-velocity of particle\n",
+      "p=deltap    #assume\n",
+      "E=math.sqrt(((p*c)**2)+((mo*(c**2))**2));    #energy(J)\n",
+      "E=E/q;      #energy(eV)\n",
+      "\n",
+      "#Result\n",
+      "print \"energy is\",round(E/10**6),\"MeV\"\n",
+      "print \"this value is much higher than experimentally obtained values of energy of electron of a radioactive nuclei i.e 4 Mev this proves that electron cannot reside within nucleus\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "energy is 10.0 MeV\n",
+        "this value is much higher than experimentally obtained values of energy of electron of a radioactive nuclei i.e 4 Mev this proves that electron cannot reside within nucleus\n"
+       ]
+      }
+     ],
+     "prompt_number": 19
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
+\ No newline at end of file
diff --git a/Engineering_Physics_/Chapter11.ipynb b/Engineering_Physics_/Chapter11.ipynb
new file mode 100755
index 00000000..9aaaa633
--- /dev/null
+++ b/Engineering_Physics_/Chapter11.ipynb
@@ -0,0 +1,194 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:6e57ef3dccc3c7eb94a4d9debf60856f056a841840d4cb2d77b1c0cffbc72c7b"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "11: Laser, holography and Fibre optics"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 11.1, Page number 317"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "n1=1.53;   #refractive index of core\n",
+      "n2=1.5;    #refractive index of cladding\n",
+      "lamda=1*10**-6;   #wavelength(m)\n",
+      "a=50*10**-6;    #core radius(m)\n",
+      "\n",
+      "#Calculation\n",
+      "NA=math.sqrt((n1**2)-(n2**2));   #numerical aperture(m)\n",
+      "V=((2*math.pi*a)*NA)/lamda;      #normalised frequency\n",
+      "M=(V**2)/2;    #number of guided mode\n",
+      "\n",
+      "#Result\n",
+      "print \"normalised frequency is\",round(V,2)\n",
+      "print \"number of guided mode is\",round(M)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "normalised frequency is 94.72\n",
+        "number of guided mode is 4486.0\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 11.2, Page number 317"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "n1=1.53;   #refractive index of core\n",
+      "n2=1.5;    #refractive index of cladding\n",
+      "lamda=1*10**-6;   #wavelength(m)\n",
+      "\n",
+      "#Calculation\n",
+      "NA=math.sqrt((n1**2)-(n2**2));   #numerical aperture(m)\n",
+      "a=(2.405*lamda)/(2*math.pi*NA);   #core radius(m)\n",
+      "\n",
+      "#Result\n",
+      "print \"core radius is less than\",round(a*10**6,2),\"micro m\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "core radius is less than 1.27 micro m\n"
+       ]
+      }
+     ],
+     "prompt_number": 7
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 11.3, Page number 317"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "NA=0.5;    #numerical aperture(m)\n",
+      "n1=1.54;   #refractive index of core\n",
+      "\n",
+      "#Calculation\n",
+      "n2=math.sqrt((n1**2)-(NA**2));    #refractive index of cladding\n",
+      "n=(n1-n2)/n1;     #change in core cladding refractive index\n",
+      "\n",
+      "#Result\n",
+      "print \"refractive index of cladding is\",round(n2,4)\n",
+      "print \"change in core cladding refractive index is\",round(n,4)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "refractive index of cladding is 1.4566\n",
+        "change in core cladding refractive index is 0.0542\n"
+       ]
+      }
+     ],
+     "prompt_number": 11
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 11.4, Page number 318"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "NA=0.5;    #numerical aperture(m)\n",
+      "n1=1.48;   #refractive index of core\n",
+      "\n",
+      "#Calculation\n",
+      "n2=math.sqrt((n1**2)-(NA**2));    #refractive index of cladding\n",
+      "alpha=math.asin(NA);     #acceptance angle(radian)\n",
+      "alpha=alpha*(180/math.pi);     #acceptance angle(degrees)\n",
+      "\n",
+      "#Result\n",
+      "print \"refractive index of cladding is\",round(n2,3)\n",
+      "print \"acceptance angle is\",alpha,\"degrees\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "refractive index of cladding is 1.393\n",
+        "acceptance angle is 30.0 degrees\n"
+       ]
+      }
+     ],
+     "prompt_number": 13
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
+\ No newline at end of file
diff --git a/Engineering_Physics_/Chapter12.ipynb.bkup b/Engineering_Physics_/Chapter12.ipynb.bkup
new file mode 100755
index 00000000..0efc0c8d
--- /dev/null
+++ b/Engineering_Physics_/Chapter12.ipynb.bkup
@@ -0,0 +1,287 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:0e9faaea32136a2f476b53b6ab2d5d2eb5330fb68ebd80aaad9bbe7ed1328c93"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "12: Radioactivity"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 12.1, Page number 351"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "M7Li3=7.018232; #mass of 7li3(amu)\n",
+      "Malpha=4.003874;  #mass of alpha particle(amu)\n",
+      "Mpr=1.008145;  #mass of proton(amu)\n",
+      "Ey=9.15;   #K.E energy of product nucleus\n",
+      "\n",
+      "#Calculation\n",
+      "#xMy -> x-mass no., M-element, y-atomic no.\n",
+      "#reaction:- 7li3 + 1H1-> 4He2 + 4He2\n",
+      "deltaM=M7Li3+Mpr-2*Malpha;  #mass defect(amu)\n",
+      "Q=deltaM*931;   #mass defect(MeV)\n",
+      "Ex=2*Ey-Q;    #K.E of incident particle(MeV)\n",
+      "\n",
+      "#Result\n",
+      "print \"kinetic energy of incident proton is\",round(Ex,4),\"MeV\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "kinetic energy of incident proton is 0.9564 MeV\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 12.2, Page number 351"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "M235U=235;   #atomic mass of 235U\n",
+      "m=10**-3;    #mass of fissions(gm)\n",
+      "N=6.023*10**23;   #avagadro number\n",
+      "Eperfi=200*10**6;   #energy per fission(eV)\n",
+      "T=10**-6;    #time(s)\n",
+      "\n",
+      "#Calculation\n",
+      "E=Eperfi*1.6*10**-19;   #energy per fission(J)\n",
+      "A=M235U; \n",
+      "P=((m*N)/A)*(E/T);    #power explosion(Watt)\n",
+      "\n",
+      "#Result\n",
+      "print \"power of explosion is\",P,\"Watt\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "power of explosion is 8.20153191489e+13 Watt\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 12.4, Page number 352"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "n=0.4;  #efficiency\n",
+      "N=6.06*10**26;   #avagadro number\n",
+      "Eperfi=200*10**6;  #energy per fission(eV)\n",
+      "P=100*10**6;    #electric power(W)\n",
+      "A=235;\n",
+      "\n",
+      "#Calculation\n",
+      "E=Eperfi*1.6*10**-19;   #energy per fission(J)\n",
+      "T=24*60*60;    #time(sec)\n",
+      "N235=P*T/(E*n);   #number of atoms in 235 kg of U235\n",
+      "m=(A*N235)/N;     #mass of 235U consumed/day(kg)\n",
+      "\n",
+      "#Result\n",
+      "print \"mass of 235U consumed/day is\",int(m*10**3),\"g\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "mass of 235U consumed/day is 261 g\n"
+       ]
+      }
+     ],
+     "prompt_number": 13
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 12.5, Page number 352"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "M2H1=2.01474;   #mass of M2H1(amu)\n",
+      "M3H1=3.01700;   #mass of M3H1(amu)\n",
+      "M1n0=1.008986;  #mass of M1n0(amu)\n",
+      "M4He2=4.003880;  #mass of M4He2(amu)\n",
+      "\n",
+      "#Calculation\n",
+      "#thermonuclear reaction in hydrogen bomb explosion \n",
+      "#2H1 + 3H1 -> 4He2 + 1n0\n",
+      "Mreac=M2H1+M3H1;   #mass of reactants(amu)\n",
+      "Mprod=M4He2+M1n0;  #mass of products(amu)\n",
+      "Q=Mreac-Mprod;   #amount of energy released per reaction(J)\n",
+      "Q=Q*931;    #amount of energy released per reaction(MeV)\n",
+      "\n",
+      "#Result\n",
+      "print \"amount of energy released per reaction is\",round(Q,3),\"MeV\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "amount of energy released per reaction is 17.572 MeV\n"
+       ]
+      }
+     ],
+     "prompt_number": 15
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 12.6, Page number 353"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "M7Li3=7.01818;   #mass of Li atom(amu)\n",
+      "M1H1=1.0081;     #mass of H atom(amu)\n",
+      "M1n0=1.009;     #mass of neutron(amu)\n",
+      "\n",
+      "#Calculation\n",
+      "BEpernu=(1/7)*((3*M1H1)+(4*M1n0)-M7Li3);  #binding energy per nucleon(J)\n",
+      "BEpernu=BEpernu*931;   #binding energy per nucleon(MeV)\n",
+      "\n",
+      "#Result\n",
+      "print \"binding energy per nucleon is\",BEpernu,\"MeV\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "binding energy per nucleon is 5.60196 MeV\n"
+       ]
+      }
+     ],
+     "prompt_number": 16
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 12.7, Page number 353"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "m=10*10**3;    #mass of U235(gm)\n",
+      "N=6.02*10**23;    #avagadro number\n",
+      "Eperfi=200*10**6;  #energy per fission(eV)\n",
+      "A=235;\n",
+      "\n",
+      "#Calculation\n",
+      "E=Eperfi*1.6*10**-19;   #energy(J)\n",
+      "T=24*60*60;   #time(s)\n",
+      "P=((m*N)/A)*(E/T);    #power output(Watt)\n",
+      "\n",
+      "#Result\n",
+      "print \"power output is\",round(P/10**9,3),\"*10**9 Watt\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "power output is 9.488 *10**9 Watt\n"
+       ]
+      }
+     ],
+     "prompt_number": 19
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
+\ No newline at end of file
diff --git a/Engineering_Physics_/Chapter2.ipynb b/Engineering_Physics_/Chapter2.ipynb
new file mode 100755
index 00000000..e5649f50
--- /dev/null
+++ b/Engineering_Physics_/Chapter2.ipynb
@@ -0,0 +1,155 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:a390c22e8bbeba1dfd4031b28f9e625838df0d3c214c564a212b1961eafc18f9"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "2: Thermoelectricity"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "Example number 2.1, Page number 54"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "Tn=285;        #neutral temperature(C)\n",
+      "Tc=-20;         #temperature at junction(C)\n",
+      "\n",
+      "#Calculation\n",
+      "Ti=(2*Tn)-Tc;     #temperature of inversion(C)\n",
+      "\n",
+      "#Result\n",
+      "print \"temperature of inversion is\",Ti,\"C\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "temperature of inversion is 590 C\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 2.2, Page number 54"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "aFe=16.65;          #value of a of Fe\n",
+      "bFe=-0.095;         #value of b of Fe\n",
+      "aAg=2.86;           #value of a of Ag\n",
+      "bAg=0.017;          #value of b of Ag\n",
+      "t=100;              #temperature(C)\n",
+      "\n",
+      "#Calculation\n",
+      "a=aFe-aAg;     #value of aFe_Ag\n",
+      "b=bFe-bAg;     #value of bFe_Ag\n",
+      "Tn=-a/b;    #neutral temperature(C)\n",
+      "EFe_Ag=(a*t)+(0.5*b*t**2);      #thermo emf of thermocouple\n",
+      "\n",
+      "#Result\n",
+      "print \"neutral temperature is\",Tn,\"C\"\n",
+      "print \"thermo emf of thermocouple is\",EFe_Ag"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "neutral temperature is 123.125 C\n",
+        "thermo emf of thermocouple is 819.0\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 2.3, Page number 54"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "#PFe=1734-4.87t\n",
+      "#PCu=136+0.95t\n",
+      "aFe_Pb=1734;\n",
+      "bFe_Pb=-4.87;\n",
+      "aCu_Pb=136;\n",
+      "bCu_Pb=0.95\n",
+      "\n",
+      "#Calculation\n",
+      "a=aFe_Pb-aCu_Pb;        #value of aFe_Cu\n",
+      "b=bFe_Pb-bCu_Pb;        #value of bFe_Cu\n",
+      "EFe_Cu=(a*t)+(0.5*b*t**2);       #thermo emf of thermocouple(microV)\n",
+      "EFe_Cu=EFe_Cu*10**-6;            #thermo emf of thermocouple(V)\n",
+      "\n",
+      "#Result\n",
+      "print \"thermo emf of thermocouple is\",EFe_Cu,\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "thermo emf of thermocouple is 0.1307 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
+\ No newline at end of file
diff --git a/Engineering_Physics_/Chapter3.ipynb b/Engineering_Physics_/Chapter3.ipynb
new file mode 100755
index 00000000..e34bf801
--- /dev/null
+++ b/Engineering_Physics_/Chapter3.ipynb
@@ -0,0 +1,112 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:5501457babf7cd881ef81ebc39845c677f30b7398a16e9160a7f32cf8c277a73"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "3: Thermionic Emission"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 3.1, Page number 67"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "S=2*10**-6;      #tungsten filament(m**2)\n",
+      "T=2000;      #temperature(K)\n",
+      "A=60.2*10**4;   #value of A(amp/m**2 K)     \n",
+      "b=52400;       #value of b \n",
+      "e=1.6*10**-19;   #electron charge(c)\n",
+      "\n",
+      "#Calculation\n",
+      "I=A*S*(T**2)*(math.exp(-(b/T)));   #electronic emission current(amp)\n",
+      "J=A*(T**2)*(math.exp(-b/T));      #emission current density(A/m**2)\n",
+      "no=J/e;          #no. of electrons emitted per unit area per sec(per m**2 sec)\n",
+      "\n",
+      "#Result\n",
+      "print \"maximum obtainable electronic emission current is\",round(I*10**6,3),\"micro amp\"\n",
+      "print \"emission current density is\",round(J,5),\"A/m**2\"\n",
+      "print \"no. of electrons emitted per unit area per sec is\",round(no/10**19,3),\"*10**19 per m**2 sec\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "maximum obtainable electronic emission current is 20.145 micro amp\n",
+        "emission current density is 10.07259 A/m**2\n",
+        "no. of electrons emitted per unit area per sec is 6.295 *10**19 per m**2 sec\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 3.2, Page number 67"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "Ip1=20;       #plate current(mA)\n",
+      "Ip2=30;       #changed plate current(mA) \n",
+      "Vp1=80;       #plate voltage(V)\n",
+      "\n",
+      "#Calculation\n",
+      "#Ip=K*(Vp^(3/2))\n",
+      "Vp2=((((Vp1)**(3/2))*Ip2)/Ip1)**(2/3);       #changed plate voltage(V)\n",
+      "\n",
+      "#Result\n",
+      "print \"plate voltage for 30mA current is\",round(Vp2,2),\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "plate voltage for 30mA current is 104.83 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
+\ No newline at end of file
diff --git a/Engineering_Physics_/Chapter4.ipynb b/Engineering_Physics_/Chapter4.ipynb
new file mode 100755
index 00000000..ee675097
--- /dev/null
+++ b/Engineering_Physics_/Chapter4.ipynb
@@ -0,0 +1,153 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:e2b842be083bc61cf1d1d9ada89de2502dedfb3d340e5f3b6d0b51d6c790688a"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "4: Ultrasonic"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 4.1, Page number 84"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "V1=343;     #velocity of air(m/s)\n",
+      "V2=1372;    #velocity f water(m/s)\n",
+      "dt=3;       #time difference(s)\n",
+      "\n",
+      "\n",
+      "#Calculation\n",
+      "S=((V1*V2)*(dt))/(V2-V1);     #distance between two ships(m)\n",
+      "\n",
+      "#Result\n",
+      "print \"distance between two ships is\",S,\"m\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "distance between two ships is 1372.0 m\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 4.2, Page number 84"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "V=1700;     #velocity of sound(m/s)\n",
+      "t=0.65;     #time(s)\n",
+      "n=0.07*10**6;     #frequency of source(Hz)\n",
+      "\n",
+      "\n",
+      "#Calculation\n",
+      "d=(V*t)/2;      #depth of sea(m)\n",
+      "lamda=V/n;      #wavelength of pulse(m)\n",
+      "\n",
+      "#Result\n",
+      "print \"depth of sea is\",d,\"m\"\n",
+      "print \"wavelength of pulse is\",round(lamda,4),\"m\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "depth of sea is 552.5 m\n",
+        "wavelength of pulse is 0.0243 m\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 4.3, Page number 84"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "P=1;     \n",
+      "l=40*10**-3;    #length of pure rod(m)\n",
+      "E=115*10**9;    #Young's modulus(N/m**2)\n",
+      "D=7.25*10**3;   #density of pure iron(kg/m**3)\n",
+      "\n",
+      "#Calculation\n",
+      "n=(P/(2*l))*math.sqrt(E/D);    #natural frequency of pure rod(Hz) \n",
+      "\n",
+      "#Result\n",
+      "print \"natural frequency of pure rod is\",round(n/10**3,1),\"kHz\"\n",
+      "print \"answer given in the book is wrong\"\n",
+      "print \"frequency of rod is more than audible range, rod can be used in magnetostriction oscillator\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "natural frequency of pure rod is 49.8 kHz\n",
+        "answer given in the book is wrong\n",
+        "frequency of rod is more than audible range, rod can be used in magnetostriction oscillator\n"
+       ]
+      }
+     ],
+     "prompt_number": 8
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
+\ No newline at end of file
diff --git a/Engineering_Physics_/Chapter5.ipynb b/Engineering_Physics_/Chapter5.ipynb
new file mode 100755
index 00000000..781fd57b
--- /dev/null
+++ b/Engineering_Physics_/Chapter5.ipynb
@@ -0,0 +1,170 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:4126f9237f2a14d1c68d93136eb798698a28e20e098ed4ce42f02e377a8fbabb"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "5: Acoustics"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 5.1, Page number 97"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "T1=1.5;     #R time for empty hall(s)\n",
+      "T2=1;       #R time with curtain cloth(s)\n",
+      "A=20;       #area of absorber(sq.m)\n",
+      "V=10*8*6;   #volume of hall(cu.m)\n",
+      "\n",
+      "#Calculation\n",
+      "a=((0.161*V)/(2*A))*((1/T2)-(1/T1));   #absorption coefficient\n",
+      "\n",
+      "#Result\n",
+      "print \"absorption coefficient is\",round(a,2),\"Sabines\"\n",
+      "print \"answer given in the book varies due to rounding off errors\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "absorption coefficient is 0.64 Sabines\n",
+        "answer given in the book varies due to rounding off errors\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 5.2, Page number 97"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "V=20*15*10;    #volume of hall(cu.m)\n",
+      "T1=3.5;        #reverberation time(s)\n",
+      "l=20;        \n",
+      "b=15;\n",
+      "h=10;      #dimensions of hall\n",
+      "am=0.5;     #absorption coefficient\n",
+      "T2=2.5;    #reverberation time after cloth use(s)\n",
+      "\n",
+      "\n",
+      "#Calculation\n",
+      "A=(0.161*V)/T1; \n",
+      "S=2*((l*b)+(b*h)+(h*l));    #surface area(sq.m)\n",
+      "sigma_a=A/S;   #average absorption coefficient of hall(o.w.u)\n",
+      "S1=(((0.161*V)/(am-sigma_a))*((1/T2)-(1/T1)));     #area of wall covered by curtain cloth(sq.m)\n",
+      "\n",
+      "#Result\n",
+      "print \"average absorption coefficient of hall is\",round(sigma_a,3),\"o.w.u\"\n",
+      "print \"area of wall covered by curtain cloth is\",round(S1,3),\"sq.m\"\n",
+      "print \"answer for area covered S1 varies due to rounding off errors\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "average absorption coefficient of hall is 0.106 o.w.u\n",
+        "area of wall covered by curtain cloth is 140.156 sq.m\n",
+        "answer for area covered S1 varies due to rounding off errors\n"
+       ]
+      }
+     ],
+     "prompt_number": 8
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 5.3, Page number 98"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "V=1450;    #volume of hall(cu.m)\n",
+      "A1=112*0.03;   #absorption due to plastered wall\n",
+      "A2=130*0.06;   #absorption due to wooden floor\n",
+      "A3=170*0.04;   #absorption due to plastered ceiling\n",
+      "A4=20*0.06;    #absorption due to wooden door\n",
+      "A5=100*1;      #absorption due to cushioned chairs\n",
+      "\n",
+      "#Calculation\n",
+      "sigma_as=A1+A2+A3+A4+A5;   #total absorption in empty hall\n",
+      "T1=(0.161*V)/sigma_as;     #reverberation time case-1(s)\n",
+      "T2=(0.161*V)/(sigma_as+(60*4.7));   #persons=60,A=4.7 case-2\n",
+      "T3=(0.161*V)/(sigma_as+(100*4.7));  #seat cushioned=100 case-3\n",
+      "\n",
+      "#Result\n",
+      "print \"reverberation time for case-1 is\",round(T1,3),\"sec\"\n",
+      "print \"reverberation time for case-2 is\",round(T2,3),\"sec\"\n",
+      "print \"reverberation time for case-3 is\",round(T3,3),\"sec\"\n",
+      "print \"answer for T3 given in the book is wrong\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "reverberation time for case-1 is 1.959 sec\n",
+        "reverberation time for case-2 is 0.582 sec\n",
+        "reverberation time for case-3 is 0.396 sec\n",
+        "answer for T3 given in the book is wrong\n"
+       ]
+      }
+     ],
+     "prompt_number": 12
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
+\ No newline at end of file
diff --git a/Engineering_Physics_/Chapter6.ipynb b/Engineering_Physics_/Chapter6.ipynb
new file mode 100755
index 00000000..7cdceb44
--- /dev/null
+++ b/Engineering_Physics_/Chapter6.ipynb
@@ -0,0 +1,287 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:c7dc6b3d9590410d93237c02edc71fc080a2b941482564691379213f8d71b12e"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "6: Semiconductors"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 6.1, Page number 133"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "V1=1.4;       #voltage1(V)\n",
+      "V2=1.5;       #voltage2(V)\n",
+      "I1=60;        #forward current for 1.4V(mA)\n",
+      "I2=85;        #forward current for 1.5V(mA)\n",
+      "\n",
+      "#Calculation\n",
+      "I1=I1*10**-3;      #forward current for 1.4V(A)\n",
+      "I2=I2*10**-3;      #forward current for 1.5V(A)\n",
+      "Rs1=V1/I1;         #static resistance for 1.4V(ohm)\n",
+      "Rs2=V2/I2;         #static resistance for 1.5V(ohm) \n",
+      "dV=V2-V1;          #change in voltage(V)\n",
+      "dI=I2-I1;          #change in current(A)\n",
+      "Rd=dV/dI;          #dynamic resistance(ohm)\n",
+      "\n",
+      "#Result\n",
+      "print \"static resistance for 1.4V is\",round(Rs1,1),\"ohm\"\n",
+      "print \"static resistance for 1.5V is\",round(Rs2,1),\"ohm\"\n",
+      "print \"dynamic resistance is\",Rd,\"ohm\"\n",
+      "print \"answer for dynamic resistance given in the book is wrong\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "static resistance for 1.4V is 23.3 ohm\n",
+        "static resistance for 1.5V is 17.6 ohm\n",
+        "dynamic resistance is 4.0 ohm\n",
+        "answer for dynamic resistance given in the book is wrong\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 6.2, Page number 134"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "IE=1;       #emitter current(mA)\n",
+      "IB=0.02;     #base current(mA)\n",
+      "\n",
+      "#Calculation\n",
+      "IC=IE-IB;      #collector current(mA)\n",
+      "beta=IC/IB;       #value of beta\n",
+      "alpha=IC/IE;      #value of alpha\n",
+      "\n",
+      "#Result\n",
+      "print \"value of beta is\",beta\n",
+      "print \"value of alpha is\",alpha"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "value of beta is 49.0\n",
+        "value of alpha is 0.98\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 6.3, Page number 134"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "alpha=0.99;        #value of alpha\n",
+      "I_CBO=0.5;         #value of ICBO(micro A)\n",
+      "\n",
+      "#Calculation\n",
+      "beta=alpha/(1-alpha);         #value of beta\n",
+      "ICEO=1/(1-alpha)*I_CBO;      #value of ICEO(micro A)\n",
+      "\n",
+      "#Result\n",
+      "print \"value of beta is\",beta\n",
+      "print \"value of ICEO is\",ICEO,\"micro A\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "value of beta is 99.0\n",
+        "value of ICEO is 50.0 micro A\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 6.4, Page number 134"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "delta_Ic=4.5-2;         #change in collector current(mA)\n",
+      "delta_Ib=80-40;         #change in base current(microA)\n",
+      "\n",
+      "#Calculation\n",
+      "delta_Ic=delta_Ic*10**-3;        #change in collector current(A)\n",
+      "delta_Ib=delta_Ib*10**-6;        #change in base current(A)\n",
+      "beta_AC=delta_Ic/delta_Ib;       #value of beta\n",
+      "alpha_AC=beta_AC/(1+beta_AC);    #value of alpha\n",
+      "\n",
+      "#Result\n",
+      "print \"value of beta is\",beta_AC\n",
+      "print \"value of alpha is\",round(alpha_AC,4)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "value of beta is 62.5\n",
+        "value of alpha is 0.9843\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 6.5, Page number 134"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "IE=1;          #emitter current(mA)\n",
+      "Oc=0.04;       #output current(mA)\n",
+      "\n",
+      "#Calculation\n",
+      "IC=1-Oc;       #collector current(mA)\n",
+      "alpha=IC/IE;      #value of alpha\n",
+      "\n",
+      "#Result\n",
+      "print \"current gain is\",alpha"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "current gain is 0.96\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 6.6, Page number 134"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "alpha=0.96;         #current gain\n",
+      "R=1;          #resistance(K ohm)\n",
+      "V=1.5;              #voltage drop(V)\n",
+      "\n",
+      "#Calculation\n",
+      "IC=V/R;        #collector current(mA)\n",
+      "IE=IC/alpha;      #emitter current(mA)\n",
+      "IB=IE-IC;         #base current(mA)\n",
+      "\n",
+      "#Result\n",
+      "print \"base current is\",IB,\"mA\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "base current is 0.0625 mA\n"
+       ]
+      }
+     ],
+     "prompt_number": 5
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
+\ No newline at end of file
diff --git a/Engineering_Physics_/Chapter7.ipynb b/Engineering_Physics_/Chapter7.ipynb
new file mode 100755
index 00000000..d5043163
--- /dev/null
+++ b/Engineering_Physics_/Chapter7.ipynb
@@ -0,0 +1,680 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:faf80c20562ef1fa5d737b0d74b9cf873ec0d412505987698b0fa170ec356db4"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "7: Thin film interference and diffraction"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 7.1, Page number 158"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "alpha=0.01;    #angle(radian)\n",
+      "n=10;        #number of fringe\n",
+      "lamda=6000*10**-8;  #wavelength(cm)\n",
+      "\n",
+      "#Calculation\n",
+      "#for dark fringe 2*u*t*cos(alpha)=n*lam\n",
+      "#t=xtan(alpha)\n",
+      "x=(n*lamda)/(2*alpha);    #distance of 10th fringe from edge of wedge(cm)\n",
+      "\n",
+      "#Result\n",
+      "print \"distance of 10th fringe from edge of wedge is\",x,\"cm\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "distance of 10th fringe from edge of wedge is 0.03 cm\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 7.2, Page number 159"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "t=5*10**-5;    #thickness of soap film(cm)\n",
+      "u=1.33; \n",
+      "\n",
+      "#Calculation\n",
+      "#for constructive interference of reflected light\n",
+      "#2*u*t*cos(r)=(2*n+1)(lam/2), where n=0,1,2,3\n",
+      "#for normal incidence r=0, cos(r)=1\n",
+      "#for n=0 lamda=lamda1\n",
+      "lamda1=4*u*t;    #wavelength for zero order(cm)\n",
+      "#for n=1 lamda=lamda2\n",
+      "lamda2=4*u*t*(1/3);    #wavelength for first order(cm)\n",
+      "#for n=2 lamda=lamda3\n",
+      "lamda3=4*u*t*(1/5);    #wavelength for second order(cm)\n",
+      "#for n=3 lamda=lamda4\n",
+      "lamda4=4*u*t*(1/7);    #wavelength for third order(cm)\n",
+      "\n",
+      "#Result\n",
+      "print \"wavelength that is strongly reflected in visible spectrum is\",lamda3*10**8,\"angstrom\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "wavelength that is strongly reflected in visible spectrum is 5320.0 angstrom\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 7.3, Page number 159"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "n=10;   #10th dark ring\n",
+      "D10=0.5;    #diameter of ring(cm)\n",
+      "lamda=5000*10**-8;    #wavelength of light(cm)   \n",
+      "\n",
+      "#Calculation\n",
+      "R=(D10**2)/(4*n*lamda);    #radius of curvature of lens(cm)\n",
+      "D50=math.sqrt(4*50*R*lamda);   #diameter of 50th dark ring(cm)\n",
+      "r50=D50/2;        #radius of 50th dark ring(cm)\n",
+      "\n",
+      "#Result\n",
+      "print \"radius of 50th dark ring is\",round(r50,2),\"cm\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "radius of 50th dark ring is 0.56 cm\n"
+       ]
+      }
+     ],
+     "prompt_number": 6
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 7.4, Page number 160"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "i=45;     #angle of incidence(degrees)\n",
+      "mew=1.33;   #refractive index\n",
+      "lamda=5000;    #wavelength(angstrom)\n",
+      "\n",
+      "#Calculation\n",
+      "i=i*(math.pi/180);    #angle of incidence(radian)\n",
+      "sin_r=math.sin(i)/mew;    #value of sin(r)\n",
+      "r=math.asin(sin_r);    #angle of refraction(radian) \n",
+      "r1=r*(180/math.pi);     #angle of refraction(degrees)\n",
+      "#for bright fringe 2*u*t*cos(r)=(2*n+1)(lamda/2)\n",
+      "#for minimum thickness n=0\n",
+      "t=lamda/(4*mew*math.cos(r));    #minimum thickness(angstrom)\n",
+      "\n",
+      "#Result\n",
+      "print \"minimum thickness of film is\",int(t),\"angstrom\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "minimum thickness of film is 1109 angstrom\n"
+       ]
+      }
+     ],
+     "prompt_number": 32
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 7.5, Page number 160"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "lamda=5500*10**-8;     #wavelength(cm)\n",
+      "V=0.2;      #volume of oil drop(cc)\n",
+      "A=100*100;   #surface area(sq.cm)\n",
+      "\n",
+      "#Calculation\n",
+      "#since both reflections occur at surface of denser medium\n",
+      "#condition for brightness for min thickness, n=1\n",
+      "#for normal incidence r=0, cos(r)=1\n",
+      "t=V/A;    #thickness of film(cm)\n",
+      "mew0=lamda/(2*t);   #refractive index of oil\n",
+      "\n",
+      "#Result\n",
+      "print \"refractive index of oil is\",mew0"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "refractive index of oil is 1.375\n"
+       ]
+      }
+     ],
+     "prompt_number": 28
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 7.6, Page number 161"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "lamda=6300;    #wavelength of light(angstrom)\n",
+      "mew=1.5;       #refractive index\n",
+      "n=10;\n",
+      "\n",
+      "#Calculation\n",
+      "#condition for dark 2*u*t=n*lam\n",
+      "#condition for bright 2*u*t=(2*n-1)(lam/2)\n",
+      "#when t=0 n=0 order dark band will come and at edge 10th bright band will come \n",
+      "t=(((2*n)-1)*(lamda))/(4*mew);   #thickness of air film(angstrom)\n",
+      "\n",
+      "#Result\n",
+      "print \"thickness of air film is\",t,\"angstrom\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "thickness of air film is 19950.0 angstrom\n"
+       ]
+      }
+     ],
+     "prompt_number": 29
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 7.7, Page number 161"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "mewg=1.5;    #refractive index of glass\n",
+      "mewo=1.3;    #refractive index of oil\n",
+      "lamda1=7000;   #wavelength(angstrom)\n",
+      "lamda2=5000;   #wavelength(angstrom)\n",
+      "r=0;     #for nth minimum\n",
+      "\n",
+      "#Calculation\n",
+      "#here reflection occurs both time at surface of denser medium\n",
+      "#condition for distructive interference in reflected side\n",
+      "#2*u*t*cos(r)=(2*n-1)(lam1/2), for nth min.\n",
+      "#2*u*t=(2*n+1)(lam1/2), n=0,1,2,3\n",
+      "#for (n+1)th min.\n",
+      "#2*u*t=(2*(n+1)+1)(lam2/2), n=0,1,2,3\n",
+      "t=(2/(4*mewo))*((lamda1*lamda2)/(lamda1-lamda2));      #thickness of layer(angstrom)\n",
+      "\n",
+      "#Result\n",
+      "print \"thickness of layer is\",int(t),\"angstrom\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "thickness of layer is 6730 angstrom\n"
+       ]
+      }
+     ],
+     "prompt_number": 31
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 7.8, Page number 162"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "Dn=1.40;    #diameter of 10th ring(cm)\n",
+      "D=1.27;     #changed diameter(cm)\n",
+      "\n",
+      "#Calculation\n",
+      "#when mew=1\n",
+      "#(Dn^2)=4*n*lam*R=(1.40^2)\n",
+      "#when mew=mew1\n",
+      "#(D^2)=(4*n*lam*R)/u1=(1.27^2)\n",
+      "mewl=((Dn**2)/(D**2));      #refractive index of liquid \n",
+      "\n",
+      "#Result\n",
+      "print \"refractive index of liquid is\",round(mewl,4)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "refractive index of liquid is 1.2152\n"
+       ]
+      }
+     ],
+     "prompt_number": 34
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 7.9, Page number 162"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "B=0.5;   #fringe width(cm)\n",
+      "mew=1.4;    #refractive index\n",
+      "\n",
+      "#Calculation\n",
+      "alpha=((math.pi*10)/(60*60*180));   #converting into radian\n",
+      "lamda=2*B*alpha*mew;   #wavelength of light(cm)\n",
+      "\n",
+      "#Result\n",
+      "print \"wavelength of light used is\",int(lamda*10**8),\"angstrom\"\n",
+      "print \"answer given in the book varies due to rounding off errors\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "wavelength of light used is 6787 angstrom\n",
+        "answer given in the book varies due to rounding off errors\n"
+       ]
+      }
+     ],
+     "prompt_number": 40
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 7.10, Page number 163"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "lamda=6000*10**-8;    #wavelengh of light(cm)\n",
+      "mew=1.5;    #refractive index\n",
+      "\n",
+      "#Calculation\n",
+      "#condition for dark fringe is 2*t=n*lam\n",
+      "#but B=(lam/(2*alpha*u))\n",
+      "#delta_t=alpha*x\n",
+      "delta_t=(10*lamda)/(2*mew);     #difference t2-t1(cm)\n",
+      "\n",
+      "#Result\n",
+      "print \"difference t2-t1 is\",delta_t,\"cm\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "difference t2-t1 is 0.0002 cm\n"
+       ]
+      }
+     ],
+     "prompt_number": 41
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 7.11, Page number 163"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "lamda=5890;   #wavelength of light(angstrom)\n",
+      "mew=1.5;    #refractive index\n",
+      "r=60;       #angle of refraction(degrees)\n",
+      "\n",
+      "#Calculation\n",
+      "#condition for dark is 2*mew*t*cos(r)=n*lamda\n",
+      "r=60*(math.pi/180);    #angle of refraction(radian)\n",
+      "#for n=1\n",
+      "t=(lamda)/(2*mew*math.cos(r));    #smallest thickness of glass plate(angstrom)\n",
+      "\n",
+      "#Result\n",
+      "print \"smallest thickness of glass plate is\",int(t),\"angstrom\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "smallest thickness of glass plate is 3926 angstrom\n"
+       ]
+      }
+     ],
+     "prompt_number": 43
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 7.13, Page number 180"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "aplusb=1/1250;    #transmission grating(lines/cm)\n",
+      "n=2;     #order of spectral line\n",
+      "theta=30;    #deviation angle(degrees)\n",
+      "\n",
+      "#Calculation\n",
+      "theta=theta*(math.pi/180);   #deviation angle(radian)\n",
+      "#(a+b)sin(theta)=n*lamda\n",
+      "lamda=(aplusb*math.sin(theta))/n;   #wavelength of spectral line(cm)\n",
+      "\n",
+      "#Result\n",
+      "print \"wavelength of spectral line is\",lamda,\"cm\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "wavelength of spectral line is 0.0002 cm\n"
+       ]
+      }
+     ],
+     "prompt_number": 45
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 7.14, Page number 180"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "lamda=5893*10**-8;    #wavelength(cm)\n",
+      "aplusb=2.54/2540;  #grating(lines/cm)\n",
+      "\n",
+      "#Calculation\n",
+      "#n=nmax, if sin(theta)=1\n",
+      "nmax=(aplusb/lamda);      #maximum order\n",
+      "\n",
+      "#Result\n",
+      "print \"maximum order is\",int(nmax)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "maximum order is 16\n"
+       ]
+      }
+     ],
+     "prompt_number": 47
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 7.15, Page number 180"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "n=2;   #second order\n",
+      "aplusb=1/5000;   #transmission grating(lines/cm)\n",
+      "lamda=5893*10**-8;      #wavelength(cm)\n",
+      "f=30;    #focal length(cm)\n",
+      "\n",
+      "#Calculation\n",
+      "dtheta=(2.5*3.14)/(180*60);    #change in angular displacement(radian)\n",
+      "#dlamda=((a+b)cos(theta)/n)dtheta\n",
+      "costheta=math.sqrt(1-(((n*lamda)/aplusb)**2));\n",
+      "dlamda=(dtheta*aplusb*costheta)/n;  #difference in wavelength(cm)\n",
+      "dl=f*dtheta;   #linear separation(cm)\n",
+      "\n",
+      "#Result\n",
+      "print \"difference in wavelength of two yellow lines\",round(dlamda*10**8),\"angstrom\"\n",
+      "print \"linear separation is\",round(dl*10**2,2),\"*10**-2 cm\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "difference in wavelength of two yellow lines 6.0 angstrom\n",
+        "linear separation is 2.18 *10**-2 cm\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 7.16, Page number 181"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "lamda1=5400*10**-8;    #wavelength1(cm)\n",
+      "lamda2=4050*10**-8;    #wavelength(cm)\n",
+      "theta=30;      #angle of diffraction(degrees)\n",
+      "\n",
+      "#Calculation\n",
+      "#nth order of lamda1 is superimposed on (n+1)th order of lamda2 for theta=30\n",
+      "#(a+b)sin(30)=n*5400*10^-8=(n+1)*4050*10^-8\n",
+      "n=(lamda2/(lamda1-lamda2));    #nth order\n",
+      "theta=30*(math.pi/180);     #angle of diffraction(radian)\n",
+      "N=math.sin(theta)/(n*lamda1);      #lines/cm in grating\n",
+      "\n",
+      "#Result\n",
+      "print \"lines/cm in grating is\",int(N),\"lines/cm\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "lines/cm in grating is 3086 lines/cm\n"
+       ]
+      }
+     ],
+     "prompt_number": 51
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
+\ No newline at end of file
diff --git a/Engineering_Physics_/Chapter8.ipynb b/Engineering_Physics_/Chapter8.ipynb
new file mode 100755
index 00000000..d9dc420b
--- /dev/null
+++ b/Engineering_Physics_/Chapter8.ipynb
@@ -0,0 +1,392 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:e5ea4ff1709764161940877bdcbbb6d4676a6eced70f445ea6f3a31c76d16a31"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "8: X-rays"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 8.1, Page number 197"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "d=4.255;     #atomic spacing(angstrom)\n",
+      "lamda=1.549;   #wavelength of K-copper line(angstrom) \n",
+      "n=1;    #theta is smallest when n=1\n",
+      "\n",
+      "\n",
+      "#Calculation\n",
+      "theta=math.asin(lamda/(2*d));   #glancing angle(radian)\n",
+      "theta=theta*(180/math.pi);      #glancing angle(degrees)\n",
+      "#max value of sin(theta)=1 for highest order\n",
+      "nmax=((2*d)/lamda);   #highest bragg's order\n",
+      "\n",
+      "\n",
+      "#Result\n",
+      "print \"smallest glancing angle is\",round(theta,4),\"degrees\"\n",
+      "print \"maximum order of reflection is\",round(nmax,3)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "smallest glancing angle is 10.4875 degrees\n",
+        "maximum order of reflection is 5.494\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 8.2, Page number 197"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "V=60*10**3;     #potential difference(volts)\n",
+      "c=3*10**8;     #velocity of light(m/sec)\n",
+      "e=1.6*10**-19;  #electron charge(coulomb)\n",
+      "lamda=0.194*10**-10;  #minimum wavelength of x-rays(m)\n",
+      "\n",
+      "#Calculation\n",
+      "h=(lamda*e*V)/c;    #planck's constant(Jsec)\n",
+      "\n",
+      "#Result\n",
+      "print \"planck's constant is\",h,\"Jsec\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "planck's constant is 6.208e-34 Jsec\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 8.3, Page number 198"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "#for 110 plane\n",
+      "h=1;\n",
+      "k=1;\n",
+      "l=0;\n",
+      "a=3;   #lattice parameter(angstrom)\n",
+      "n=1;\n",
+      "theta=12.5;    #glancing angle(degrees)\n",
+      "\n",
+      "#Calculation\n",
+      "theta1=theta*(math.pi/180);  #glancing angle(radian)\n",
+      "d110=(a/math.sqrt((h**2)+(k**2)+(l**2)));   \n",
+      "lamda=2*d110*math.sin(theta1)/n;   #wavelength of x-ray(angstrom)\n",
+      "nmax=((2*d110)/lamda);    #highest order possible\n",
+      "\n",
+      "#Result\n",
+      "print \"wavelength of x-ray beam is\",round(lamda,3),\"angstrom\"\n",
+      "print \"highest bragg's order possible is\",int(nmax)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "wavelength of x-ray beam is 0.918 angstrom\n",
+        "highest bragg's order possible is 4\n"
+       ]
+      }
+     ],
+     "prompt_number": 11
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 8.4, Page number 198"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "d=2.81*10**-10;     #interplanar spacing(m)\n",
+      "theta=14;   #glancing angle(degrees) \n",
+      "e=1.6*10**-19;   #electron charge(c)\n",
+      "V=9100;    #voltage(V)\n",
+      "n=1;\n",
+      "c=3*10**8;   #velocity of light(m/sec)\n",
+      "\n",
+      "#Calculation\n",
+      "theta=theta*(math.pi/180);  #glancing angle(radian)\n",
+      "lamda=2*d*math.sin(theta)/n;   #minimum wavelength\n",
+      "h=(lamda*e*V)/c;        #planck's constant(Jsec)\n",
+      "\n",
+      "#Result\n",
+      "print \"planck's constant is\",round(h*10**34,4),\"*10**-34 Jsec\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "planck's constant is 6.5986 *10**-34 Jsec\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 8.5, Page number 198"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "thetaA=30;     #glancing angle for line A(degrees)\n",
+      "lamdaB=0.97;    #wavelength of line B(angstrom)\n",
+      "thetaB=60;     #glancing angle for line B(degrees)\n",
+      "\n",
+      "#Calculation\n",
+      "#for line A-> 2*d*sin(thetaA)=lamdaA(n=1)\n",
+      "thetaA=thetaA*(math.pi/180);  #glancing angle for line A(radian)\n",
+      "#for line B-> 2*d*sin(thetaB)=3*lamdaB(n=3)\n",
+      "thetaB=thetaB*(math.pi/180);  #glancing angle for line B(radian) \n",
+      "d=(3*lamdaB)/(2*math.sin(thetaB));    #interplanar spacing(angstrom)\n",
+      "lamdaA=2*d*math.sin(thetaA);   #wavelength of line A(angstrom)\n",
+      "\n",
+      "#Result\n",
+      "print \"wavelength of line A is\",round(lamdaA,2),\"angstrom\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "wavelength of line A is 1.68 angstrom\n"
+       ]
+      }
+     ],
+     "prompt_number": 14
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 8.6, Page number 199"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "a=3.615;    #lattice constant(angstrom)\n",
+      "h=1;\n",
+      "k=1;\n",
+      "l=1;\n",
+      "theta=21.7;   #glancing angle(degrees)\n",
+      "\n",
+      "#Calculation\n",
+      "d111=a/math.sqrt(h**2+k**2+l**2);   #interplanar spacing(angstrom)\n",
+      "theta=theta*(math.pi/180);   #glancing angle(radian)\n",
+      "lamda=2*d111*math.sin(theta);   #wavelength of X-rays(angstrom)\n",
+      "\n",
+      "#Result\n",
+      "print \"wavelength of X-rays is\",round(lamda,3),\"angstrom\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "wavelength of X-rays is 1.543 angstrom\n"
+       ]
+      }
+     ],
+     "prompt_number": 16
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 8.7, Page number 199"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "V=50*10**3;   #voltage(V)\n",
+      "n=4;    #FCC crystal\n",
+      "m=74.6;  #molecular mass(kg)\n",
+      "N=6.02*10**26;    #avagadro number(per kg mol)\n",
+      "rho=1.99*10**3;   #density(kg/m**3) \n",
+      "\n",
+      "#Calculation\n",
+      "lamda=(12400/V);   #short wavelength(angstrom)\n",
+      "a=(((n*m)/(N*rho))**(1/3));   #lattice constant(m)\n",
+      "#for kcl ionic crystal\n",
+      "d=a/2;\n",
+      "sintheta=lamda*10**-10/(2*d);   #value of sintheta\n",
+      "theta=math.asin(sintheta);    #glancing angle(radian)\n",
+      "theta=theta*(180/math.pi);      #glancing angle(degrees)\n",
+      "\n",
+      "#Result\n",
+      "print \"short wavelength of spectrum from tube is\",lamda,\"angstrom\"\n",
+      "print \"glancing angle for that wavelength is\",round(theta,4),\"degrees\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "short wavelength of spectrum from tube is 0.248 angstrom\n",
+        "glancing angle for that wavelength is 2.2589 degrees\n"
+       ]
+      }
+     ],
+     "prompt_number": 28
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 8.8, Page number 199"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "theta1=5.4;    #glancing angle(degrees)\n",
+      "theta2=7.6;    #glancing angle(degrees)\n",
+      "theta3=9.4;    #glancing angle(degrees) \n",
+      "\n",
+      "#Calculation\n",
+      "#from bragg's law 2*d*sin(theta)=n*lamda, n=1\n",
+      "theta1=theta1*(math.pi/180);   #glancing angle(radian)\n",
+      "theta2=theta2*(math.pi/180);   #glancing angle(radian)\n",
+      "theta3=theta3*(math.pi/180);   #glancing angle(radian)\n",
+      "d100=lamda/2*math.sin(theta1);  #interplanar spacing\n",
+      "d110=lamda/2*math.sin(theta2);  #interplanar spacing\n",
+      "d111=lamda/2*math.sin(theta3);  #interplanar spacing\n",
+      "\n",
+      "#Result\n",
+      "print \"ratio of interplanar spacing (1/d100):(1/d110):(1/d111)=\",round(math.sin(theta1),4),\":\",round(math.sin(theta2),4),\":\",round(math.sin(theta3),4)\n",
+      "print \"as ratio (1/d100):(1/d110):(1/d111)=1:sqrt(2):sqrt(3). this relation is valid for simple cubic systems. therefore, this is a simple cubic crystal\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "ratio of interplanar spacing (1/d100):(1/d110):(1/d111)= 0.0941 : 0.1323 : 0.1633\n",
+        "as ratio (1/d100):(1/d110):(1/d111)=1:sqrt(2):sqrt(3). this relation is valid for simple cubic systems. therefore, this is a simple cubic crystal\n"
+       ]
+      }
+     ],
+     "prompt_number": 34
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
+\ No newline at end of file
diff --git a/Engineering_Physics_/Chapter9.ipynb b/Engineering_Physics_/Chapter9.ipynb
new file mode 100755
index 00000000..9aff9ae1
--- /dev/null
+++ b/Engineering_Physics_/Chapter9.ipynb
@@ -0,0 +1,654 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:12b212fa69742f446e6918a565a72f52e2d9500de27031b4c21c41162a940ee1"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "9: Motion of the charged particle in electric and magnetic field"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 9.1, Page number 230"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "L=1.33*10**-22;   #angular momentum(kg m**2/sec)\n",
+      "B=0.025;    #magnetic field(Wb/m**2)\n",
+      "m=6.68*10**-27;   #mass of alpha particle(kg)\n",
+      "q=3.2*10**-19;   #charge of alpha particle(c)\n",
+      "e=1.6*10**-19;   #charge of electron(c)\n",
+      "\n",
+      "#Calculation\n",
+      "w=(B*q)/m;   #angular velocity\n",
+      "E=0.5*L*w;   #KE of particle(J)\n",
+      "E=E/e;     #KE of particle(eV)\n",
+      "\n",
+      "#Result\n",
+      "print \"KE of particle is\",round(E,2),\"eV\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "KE of particle is 497.75 eV\n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 9.2, Page number 230"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "R=0.35;   #radius of cyclotron(m)\n",
+      "n=1.38*10**7;   #frequency(Hz)\n",
+      "m=1.67*10**-27;  #mass of proton(kg)\n",
+      "q=1.6*10**-19;   #charge of proton(c)\n",
+      "\n",
+      "#Calculation\n",
+      "B=(2*math.pi*n*m)/q;   #magnetic field induction(Wb/m**2)\n",
+      "E=((B**2)*(q**2)*(R**2))/(2*m);   #maximum energy of proton(J)\n",
+      "E=E/q;    #maximum energy of proton(eV)\n",
+      "\n",
+      "#Result\n",
+      "print \"magnetic field induction is\",round(B,3),\"Wb/m**2\"\n",
+      "print \"maximum energy of proton is\",round(E/10**6,1),\"MeV\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "magnetic field induction is 0.905 Wb/m**2\n",
+        "maximum energy of proton is 4.8 MeV\n"
+       ]
+      }
+     ],
+     "prompt_number": 7
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 9.3, Page number 231"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "m=9.1*10**-31;   #mass of electron(kg)\n",
+      "e=1.6*10**-19;   #charge of electron(c)\n",
+      "V=1000;   #potential difference(V)\n",
+      "B=1.19*10**-3;   #magnetic field of induction(Wb/m**2)\n",
+      "\n",
+      "#Calculation\n",
+      "#due to potential difference V, electron is accelerated\n",
+      "#eV=0.5*m*(v^2)\n",
+      "#due to transverse magnetic field B electron moves in circular path of radius R\n",
+      "#(m*(v^2))/R=BeV\n",
+      "v=math.sqrt((2*e*V)/m);   #velocity(m/sec)\n",
+      "R=(m*v)/(B*e);   #radius of electron trajectory(m)\n",
+      "L=m*v*R;    #angular momentum(kg m**2/sec)\n",
+      "\n",
+      "#Result\n",
+      "print \"radius of electron trajectory is\",round(R*100,3),\"cm\"\n",
+      "print \"angular momentum of electron is\",round(L/10**-28,2),\"*10**-28 kg m**2/sec\"\n",
+      "print \"answer for angular momentum varies due to rounding off errors\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "radius of electron trajectory is 8.962 cm\n",
+        "angular momentum of electron is 15294.12 *10**-28 kg m**2/sec\n",
+        "answer for angular momentum varies due to rounding off errors\n"
+       ]
+      }
+     ],
+     "prompt_number": 16
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 9.4, Page number 231"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "vx=1.7*10**7;   #horizontal velociy(m/sec)\n",
+      "Ey=3.4*10**4;   #electric field(V/m)\n",
+      "x=3*10**-2;     #horizontal displacement(m)\n",
+      "m=9.1*10**-31;   #mass of electron(kg)\n",
+      "e=1.6*10**-19;   #charge of electron(c)\n",
+      "\n",
+      "#Calculation\n",
+      "t=x/vx;   #time(sec)\n",
+      "#y=0.5*ay*(t^2)\n",
+      "ay=(e*Ey)/m;    #acceleration(m/sec**2)\n",
+      "y=0.5*ay*(t**2);   #vertical displacement(m)\n",
+      "Bz=Ey/vx;   #magnitude of magnetic field(Wb/m**2) \n",
+      "\n",
+      "#Result\n",
+      "print \"vertical displacement of electron is\",round(y*100,4),\"cm\"\n",
+      "print \"answer varies due to rounding off errors\"\n",
+      "print \"magnitude of magnetic field is\",Bz,\"Wb/m**2\"\n",
+      "print \"direction of field is upward as Ey is downward\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "vertical displacement of electron is 0.9308 cm\n",
+        "answer varies due to rounding off errors\n",
+        "magnitude of magnetic field is 0.002 Wb/m**2\n",
+        "direction of field is upward as Ey is downward\n"
+       ]
+      }
+     ],
+     "prompt_number": 23
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 9.5, Page number 232"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "m=1.67*10**-27;      #mass of proton(kg)\n",
+      "q=1.6*10**-19;    #charge of proton(c)\n",
+      "B=0.5;     #magnetic field(Wb/m**2)\n",
+      "R=1;     #radius of cyclotron(m)\n",
+      "\n",
+      "\n",
+      "#Calculation\n",
+      "n=((B*q)/(2*math.pi*m));   #frequency of oscillation voltage(Hz)\n",
+      "E=((B**2)*(q**2)*(R**2))/(2*m);    #maximum energy of proton(J)\n",
+      "E=E/q;    #maximum energy of proton(eV)\n",
+      "\n",
+      "#Result\n",
+      "print \"frequency of oscillation voltage is\",round(n/10**6,3),\"MHz\"\n",
+      "print \"maximum energy of proton is\",round(E/10**6,3),\"MeV\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "frequency of oscillation voltage is 7.624 MHz\n",
+        "maximum energy of proton is 11.976 MeV\n"
+       ]
+      }
+     ],
+     "prompt_number": 31
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 9.6, Page number 232"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "q=3.2*10**-19  #charge of a9lpha particle(c)\n",
+      "m=6.68*10**-27;  #mass(kg) \n",
+      "B=1.5;   #magnetic field(Wb/m**2)\n",
+      "v=7.263*10**6;   #velocity(m/s) \n",
+      "\n",
+      "#Calculation\n",
+      "F=B*q*v;    #force on particle(N)\n",
+      "T=(2*math.pi*m)/(B*q);   #periodic time(sec)\n",
+      "n=1/T;    #resonance frequency(Hz)\n",
+      "\n",
+      "#Result\n",
+      "print \"force on particle is\",round(F*10**13,2),\"*10**-13 N\"\n",
+      "print \"periodic time is\",round(T*10**8,3),\"*10**-8 sec\"\n",
+      "print \"answer for periodic time varies due to rounding off errors\"\n",
+      "print \"resonance frequency is\",round(n/10**6,2),\"MHz\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "force on particle is 34.86 *10**-13 N\n",
+        "periodic time is 8.744 *10**-8 sec\n",
+        "answer for periodic time varies due to rounding off errors\n",
+        "resonance frequency is 11.44 MHz\n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 9.7, Page number 233"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "n=1.2*10**7;   #frequency(Hz)\n",
+      "mp=1.67*10**-27;   #mass of proton(kg)\n",
+      "qp=1.6*10**-19;    #charge of proton(c)\n",
+      "R=0.5;   #radius(m)\n",
+      "malp=6.68*10**-27;   #mass of alpha particle(kg)\n",
+      "\n",
+      "#Calculation\n",
+      "Bp=(2*math.pi*mp*n)/qp;   #flux density for proton(Wb/m**2)\n",
+      "Ep=((Bp**2)*(qp**2)*(R**2))/(2*mp);   #energy of proton(J)\n",
+      "Ep=Ep/qp;          #energy of proton(eV)\n",
+      "qalp=2*qp;    #charge of alpha particle(c)\n",
+      "Balp=(2*math.pi*malp*n)/qalp;    #flux density of alpha particle(Wb/m**2)\n",
+      "Ealp=((Balp**2)*(qalp**2)*(R**2))/(2*malp);   #energy of alpha particle(J)\n",
+      "Ealp=Ealp/qp;    #energy of alpha particle(eV)\n",
+      "\n",
+      "#Result\n",
+      "print \"flux density for proton is\",round(Bp,5),\"Wb/m**2\"\n",
+      "print \"flux density for alpha particle is\",round(Balp,4),\"Wb/m**2\"\n",
+      "print \"energy of proton is\",round(Ep/10**6,2),\"MeV\"\n",
+      "print \"energy of alpha particle is\",round(Ealp/10**6,2),\"MeV\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "flux density for proton is 0.78697 Wb/m**2\n",
+        "flux density for alpha particle is 1.5739 Wb/m**2\n",
+        "energy of proton is 7.42 MeV\n",
+        "energy of alpha particle is 29.67 MeV\n"
+       ]
+      }
+     ],
+     "prompt_number": 42
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 9.8, Page number 233"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "e=1.6*10**-19;   #charge of electron(c) \n",
+      "me=9.1*10**-31;  #mass of electron(kg)\n",
+      "malp=6.68*10**-27;  #mass of alpha particle(kg)\n",
+      "B=0.05;  #magnetic field(Wb/m**2)\n",
+      "V=20*10**3;    #potential difference(V)\n",
+      "\n",
+      "#Calculation\n",
+      "q=2*e;    #charge of alpha particle(c)\n",
+      "#v=sqrt((2*q*V)/m)\n",
+      "#R=(1/B)*sqrt((2*m*V)/q)\n",
+      "Re=(1/B)*math.sqrt((2*me*V)/e);   #radius of electron(m)\n",
+      "Ralp=(1/B)*math.sqrt((2*malp*V)/q);   #radius of alpha particle(m)\n",
+      "S=2*Ralp-2*Re;  #linear separation between two particles(m)\n",
+      "\n",
+      "#Result\n",
+      "print \"linear separation between two particles on common boundary wall is\",round(S*100,1),\"cm\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "linear separation between two particles on common boundary wall is 113.7 cm\n"
+       ]
+      }
+     ],
+     "prompt_number": 45
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 9.9, Page number 234"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "V1=200;    #potential difference(V)\n",
+      "i=60;   #angle(degrees)\n",
+      "r=45;   #angle(degrees)\n",
+      "\n",
+      "#Calculation\n",
+      "#electrostatic focusing condition (sini/sinr)=(v2/v1)=sqrt(V2/V1)\n",
+      "#0.5mv2=eV\n",
+      "i=i*(math.pi/180);  #angle(radian)\n",
+      "r=r*(math.pi/180);  #angle(radian)\n",
+      "V2=V1*((math.sin(i)/math.sin(r))**2);   #potential difference(V)\n",
+      "pd=V2-V1;   #potential difference(V)\n",
+      "\n",
+      "#Result\n",
+      "print \"potential difference between two regions is\",pd,\"V\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "potential difference between two regions is 100.0 V\n"
+       ]
+      }
+     ],
+     "prompt_number": 46
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 9.10, Page number 235"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "E=250;    #electric field(V/m)\n",
+      "R=10**-8;  #radius of drop(m)\n",
+      "rho=10**3;   #density of water(kg/m**3)\n",
+      "\n",
+      "#Calculation\n",
+      "#F=mg=qE\n",
+      "m=(4/3)*math.pi*(R**3)*rho;    #mass of water drop(kg)\n",
+      "W=m*9.8;   #weight of drop\n",
+      "q=W/E;     #charge on water drop(C)\n",
+      "\n",
+      "#Result\n",
+      "print \"charge on water drop is\",round(q*10**21,3),\"*10**-21 C\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "charge on water drop is 0.164 *10**-21 C\n"
+       ]
+      }
+     ],
+     "prompt_number": 7
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 9.11, Page number 235"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "e=1.6*10**-19;   #charge of electron(c)\n",
+      "v=5*10**5;   #velocity(m/s)\n",
+      "B=0.3;    #flux density(Wb/m**2)\n",
+      "N=6.025*10**26;   #avagadro number\n",
+      "M72=72/N;    #mass(kg)\n",
+      "M74=74;    #mass(kg)\n",
+      "\n",
+      "#Calculation\n",
+      "R72=(M72*v)/(B*e);    #radius(m)\n",
+      "R74=(R72/72)*M74;    #radius(m)\n",
+      "S=2*(R74-R72);   #linear separation of two lines(m)\n",
+      "\n",
+      "#Result\n",
+      "print \"linear separation of two lines is\",round(S,3),\"m\"\n",
+      "print \"answer given in the book is wrong\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "linear separation of two lines is 0.069 m\n",
+        "answer given in the book is wrong\n"
+       ]
+      }
+     ],
+     "prompt_number": 58
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 9.12, Page number 236"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "l=5*10**-2;  #length(m)\n",
+      "d=0.3;   #distance of screen from end of magnetic field(m)\n",
+      "y=0.01;   #deflection on screen(m)\n",
+      "m=9.1*10**-31;  #mass of electron(kg)\n",
+      "e=1.6*10**-19;  #charge of electron(C)\n",
+      "Va=1000;   #anode voltage(V)\n",
+      "\n",
+      "#Calculation\n",
+      "D=d+(l/2);   #distance(m)\n",
+      "B=(y/(D*l))*math.sqrt((2*m*Va)/e);   #flux density(Wb/m**2)\n",
+      "\n",
+      "#Result\n",
+      "print \"flux density is\",round(B*10**6,1),\"*10**-6 Wb/m**2\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "flux density is 65.6 *10**-6 Wb/m**2\n"
+       ]
+      }
+     ],
+     "prompt_number": 8
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Example number 9.13, Page number 236"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "#importing modules\n",
+      "import math\n",
+      "from __future__ import division\n",
+      "\n",
+      "#Variable declaration\n",
+      "e=1.6*10**-19;     #charge of electron(C)\n",
+      "Va=150;    #potential difference(V)\n",
+      "m=9.1*10**-31;  #mass of electron(kg)\n",
+      "V=20;     #potential(V)\n",
+      "D=1/2;\n",
+      "d=10**-2;   #distance of seperation(m)\n",
+      "l=10*10**-2;    #length(m)\n",
+      "\n",
+      "#Calculation\n",
+      "vx=math.sqrt((2*e*Va)/m);    #velocity of electron reacting the field(m/s)\n",
+      "ay=(e/m)*(V/d);    #acceleration due to deflecting field(m/s**2)\n",
+      "vy=ay*(l/vx);    #final velocity attained by deflecting field(m/s)\n",
+      "theta=math.atan(vy/vx);    #angle of deflection(radian)\n",
+      "thetaD=theta*(180/math.pi);   #angle of deflection(degrees)\n",
+      "Y=D*math.tan(theta);     #deflection on screen(m)\n",
+      "S=(Y/V);     #deflection senstivity(m/V)\n",
+      "\n",
+      "\n",
+      "#Result\n",
+      "print \"velocity of electron reacting the field is\",round(vx/10**6,2),\"*10**6 m/s\"\n",
+      "print \"acceleration due to deflecting field is\",round(ay*10**-14,3),\"*10**14 m/s**2\"\n",
+      "print \"final velocity attained by deflecting field is\",round(vy/10**6,1),\"*10**6 m/s\"\n",
+      "print \"angle of deflection is\",round(thetaD,2),\"degrees\"\n",
+      "print \"answer varies due to rounding off errors\"\n",
+      "print \"deflection on screen is\",round(Y,2),\"m\"\n",
+      "print \"deflection senstivity is\",round(S,4),\"m/V\"\n",
+      "print \"answer varies due to rounding off errors\""
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "velocity of electron reacting the field is 7.26 *10**6 m/s\n",
+        "acceleration due to deflecting field is 3.516 *10**14 m/s**2\n",
+        "final velocity attained by deflecting field is 4.8 *10**6 m/s\n",
+        "angle of deflection is 33.69 degrees\n",
+        "answer varies due to rounding off errors\n",
+        "deflection on screen is 0.33 m\n",
+        "deflection senstivity is 0.0167 m/V\n"
+       ]
+      }
+     ],
+     "prompt_number": 11
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
+\ No newline at end of file
diff --git a/Engineering_Physics_/README.txt b/Engineering_Physics_/README.txt
new file mode 100755
index 00000000..b121a766
--- /dev/null
+++ b/Engineering_Physics_/README.txt
@@ -0,0 +1,10 @@
+Contributed By: SPANDANA ARROJU
+Course: others
+College/Institute/Organization: JNAFAU
+Department/Designation: Applied Arts
+Book Title: Engineering Physics 
+Author: Uma Mukherji
+Publisher: Narosa Publishing House, New Delhi
+Year of publication: 2003
+Isbn: 81-7319-240-5
+Edition: 1
+\ No newline at end of file
diff --git a/Engineering_Physics_/screenshots/11.png b/Engineering_Physics_/screenshots/11.png
new file mode 100755
index 00000000..74759f5f
--- /dev/null
+++ b/Engineering_Physics_/screenshots/11.png
diff --git a/Engineering_Physics_/screenshots/22.png b/Engineering_Physics_/screenshots/22.png
new file mode 100755
index 00000000..ec09c65c
--- /dev/null
+++ b/Engineering_Physics_/screenshots/22.png
diff --git a/Engineering_Physics_/screenshots/33.png b/Engineering_Physics_/screenshots/33.png
new file mode 100755
index 00000000..a4da4f79
--- /dev/null
+++ b/Engineering_Physics_/screenshots/33.png