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+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 2 Antenna Fundamentals"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.1 Calculation of Etheta"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      " Distance between point's is m 200 m\n",
+      " the wavelength is  10 m\n",
+      " the current element is  0.00030000000000000003 A/m\n",
+      " Etheta value is V/m 0.2826\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "# Etheta = 60∗ pi ∗ I ( dl / lambda ) ∗ ( sin(theta) / r) where thetha = 90\n",
+    "r =200;\n",
+    "print ( \" Distance between point's is m\" ,r ,'m') \n",
+    "lam =10;\n",
+    "print ( \" the wavelength is \" , lam ,'m') ;\n",
+    "idl =3*10**-4;\n",
+    "print ( \" the current element is \" , idl ,\"A/m\") ;\n",
+    "Etheta =60*3.14*3*10** -3/2\n",
+    "print(\" Etheta value is V/m\",Etheta)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.2 Calculation of directive gain"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "radiation resistance is  72 ohm\n",
+      "the Loss resistance is  8 ohm\n",
+      "the power gain of antenna is  30\n",
+      "the Directivity gain is  33.333333333333336\n",
+      "the Directivity gain in db is given by  15.228787452803376\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#etta=Prad/Prad+Ploss=Rrad/Rrad+Rloss\n",
+    "Rrad=72;\n",
+    "print(\"radiation resistance is \",Rrad,\"ohm\");\n",
+    "Rloss=8;\n",
+    "ettar=72/(72+8);\n",
+    "print(\"the Loss resistance is \",Rloss,\"ohm\");\n",
+    "Gpmax=30;\n",
+    "print(\"the power gain of antenna is \",Gpmax);\n",
+    "Gdmax=Gpmax/ettar;\n",
+    "Gdmax1=10 *math.log10(Gdmax);#in db\n",
+    "print(\"the Directivity gain is \",Gdmax);\n",
+    "print(\"the Directivity gain in db is given by \",Gdmax1);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.3 Radiation Resistance calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "the elemental length is given by  0.1\n",
+      "the radiation resistance is  7.895683520871488 ohm\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Rrad=80*pi^2*(dl/lambda)^2\n",
+    "dl=0.1;\n",
+    "print(\"the elemental length is given by \",dl);\n",
+    "Rrad=80*(math.pi)**2*(0.1)**2;\n",
+    "print(\"the radiation resistance is \",Rrad,\"ohm\");\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.4 Rms current calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "the wavelength is  3.0 m\n",
+      "the Radiated power is  100 W\n",
+      "the elemental length is  0.01 m\n",
+      "the Irms current is  106.76438151257656 A\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Prad=80*(pi)**2*(dl/lambda)*(Irms)**2;\n",
+    "frequency=100*10**6;\n",
+    "lamda=(3*10**8)/(100*10**6); #lamda=c/f;\n",
+    "print(\"the wavelength is \",lamda,\"m\");\n",
+    "Prad=100;\n",
+    "print(\"the Radiated power is \",Prad,\"W\");\n",
+    "dl=0.01;\n",
+    "print(\"the elemental length is \",dl,\"m\");\n",
+    "Irms2=(3/0.01)**2*100/(80*(math.pi)**2);\n",
+    "Irms=math.sqrt(Irms2);\n",
+    "print(\"the Irms current is \",Irms,\"A\")"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.5 Effective aperture calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 8,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "the electric field is  0.05 V/m\n",
+      "the average power is  3.315727981081154e-06 W\n",
+      "the maximum effective aperture area is  0.603318250377074 m^2\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Pavg=0.5*|E|^2/etta0,Prmax=2*10^-6W,Aem=Prmax/Pavg\n",
+    "\n",
+    "E=50*10**-3;\n",
+    "Etta0=120*(math.pi);\n",
+    "print(\"the electric field is \",E,\"V/m\");\n",
+    "Pavg=0.5*(50*10**-3)**2/(120*(math.pi));\n",
+    "print(\"the average power is \",Pavg,\"W\");\n",
+    "Aem=(2*10**-6)/(3.315*10**-6);\n",
+    "print(\"the maximum effective aperture area is \",Aem,\"m^2\");\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.6 Aperture area calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The electric field is 5.000000e-02 V/m\n",
+      "The average power is 3.31573e-06 W\n",
+      "The maximum effective aperture area is 0.603318 m^2\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Pavg=0.5*|E|^2/etta0,Prmax=2*10^-6W,Aem=Prmax/Pavg\n",
+    "\n",
+    "E=50*10**-3;\n",
+    "Etta0=120*(math.pi);\n",
+    "print(\"The electric field is %e V/m\"%E);\n",
+    "Pavg=0.5*(50*10**-3)**2/(120*(math.pi));\n",
+    "print(\"The average power is %g W\"%Pavg);\n",
+    "Aem=(2*10**-6)/(3.315*10**-6);\n",
+    "print(\"The maximum effective aperture area is %g m^2\"%Aem);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.7 Transmitted power calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The wavelength is 0.1 m\n",
+      "The transmitter power is 36.8116 W\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#GT=GR=Antilog[GT or Gr(in db)/10]=31.622*10^3\n",
+    "#1 mile=1609.35 m\n",
+    "\n",
+    "freq=3*10**9;\n",
+    "d=48280.5;#30miles*1609.35\n",
+    "lamda=(3*10**8)/(3*10**9);\n",
+    "print(\"The wavelength is %g m\"%lamda);\n",
+    "Pt=(10**-3)*((4*(math.pi)*48280.5)/0.1)**2*(1/(31.622*10**3)**2);#Pr=Pt(GR*GT*(lamda/4*pi*d)^2),Pr=1mW\n",
+    "print(\"The transmitter power is %g W\"%Pt);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.8 Noise temperature calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "F is given by 1.2882\n",
+      "Effective noise temperature is 83.578 K\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#T0=290k,room temperature\n",
+    "\n",
+    "F=1.2882;\n",
+    "print(\"F is given by %g\"%F);\n",
+    "Te=(1.2882-1)*290;#Te=(F-1)T0\n",
+    "print(\"Effective noise temperature is %g K\"%Te);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.9 Average power calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The average power is 0.365 W\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Etheta=60Im/r*(cos(pi/2cos(theta))/sin(theta));\n",
+    "#theta=90\n",
+    "#Pavg=Rrad*Irms^2;\n",
+    "#Irms=Im/sqrt(2)\n",
+    "\n",
+    "Im=100*10**-3;\n",
+    "r=100\n",
+    "Etheta=(60*10**-3);\n",
+    "H=(60*10**-3)/(120*(math.pi));\n",
+    "Pavg=73*(10**-1/math.sqrt(2))**2;#Rrad=73ohm for half wave dipole\n",
+    "print(\"The average power is %g W\"%Pavg);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.10 Average power calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The average power is 22.9746 W\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Rrad=36.5ohm\n",
+    "#Irms=Im/sqrt(2)\n",
+    "\n",
+    "Im=1.22;#on applying Kvl\n",
+    "Pavg=36.5*(1.122/math.sqrt(2))**2;\n",
+    "print(\"The average power is %g W\"%Pavg);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.11 power calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiated Power is 0.157914 W\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Hphi=Im*dl*sin(theta)/(2*lamda*r);\n",
+    "#for Hertzian Dipole\n",
+    "\n",
+    "Hphi=5*10**-6;\n",
+    "lamda=1;#assume\n",
+    "dl=0.04;\n",
+    "Im=(5*10**-6)*2*(2*10**3)/(0.04);\n",
+    "Irms=Im/(math.sqrt(2));\n",
+    "Prad=80*(math.pi)**2*(0.04)**2*(Irms)**2;\n",
+    "print(\"The radiated Power is %g W\"%Prad);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.12 Power calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiated power is 0.144096 W\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#For Half wave Dipole\n",
+    "#Hphi=Im/(2*pi*r)*cos(pi/2*cos(theta)/sin(theta))\n",
+    "#Rrad=73 ohm\n",
+    "\n",
+    "Hphi=5*10**-6;\n",
+    "r=2*10**3;\n",
+    "Im=(5*10**-6)*(4*(math.pi)*10**3);\n",
+    "Prad=73*(Im/math.sqrt(2))**2;\n",
+    "print(\"The radiated power is %g W\"%Prad);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.13 power calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 8,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiated power is 0.0720481 W\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#For quarter wave monopole\n",
+    "#Rrad=36.5 ohm\n",
+    "\n",
+    "Im=20*(math.pi)*10**-3;#from previous problem\n",
+    "Prad=36.5*((20*(math.pi)*10**-3)/math.sqrt(2))**2;\n",
+    "print(\"The radiated power is %g W\"%Prad);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.14 Dipole length calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 9,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The length of the dipole antenna is 3 m\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#lamda=velocity/frequency\n",
+    "\n",
+    "frequency=50*10**6;\n",
+    "lamda=3*10**8/frequency;\n",
+    "leng=lamda/2;\n",
+    "print(\"The length of the dipole antenna is %d m\"%leng);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.15 Current calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 10,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The current through the dipole is 0.0833333 A\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Etheta=60*Im*cos(pi/2*cos(theta)/sin(theta))/r\n",
+    "\n",
+    "r=500*10**3;\n",
+    "Etheta=10*10**-6;\n",
+    "Im=Etheta*r/60;\n",
+    "print(\"The current through the dipole is %g A\"%Im);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.16 power calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 11,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiated power is 3.04045 W\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#for half wave dipole\n",
+    "\n",
+    "Pavg=0.5*73*0.0833;#Rrad*Irms^2;Rrad=73 ohm\n",
+    "print(\"The radiated power is %g W\"%Pavg);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.17 Directivity calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 12,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiated power is 0.38 W\n",
+      "The directivity is 16.5347\n",
+      "The directivity is 20.944\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#efficiency=Prad/Pinput\n",
+    "#efficiency=0.95,Umax=0.5W/sr,D=Umax/[Prad/4*pi];\n",
+    "\n",
+    "#part (i)\n",
+    "Pinput=0.4;\n",
+    "n=0.95;\n",
+    "Umax=0.5;\n",
+    "Prad=n*Pinput;\n",
+    "print(\"The radiated power is %g W\"%Prad);\n",
+    "D=0.5/(0.38/(4*(math.pi)));\n",
+    "print(\"The directivity is %g\"%D);\n",
+    "\n",
+    "#part(ii)\n",
+    "Prad=0.3;\n",
+    "D=0.5/(0.3/(4*(math.pi)));\n",
+    "print(\"The directivity is %g\"%D);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.18 Efield calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 13,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiated power is 0.215286 W\n",
+      "E2 = 2.11906e-07\n",
+      "The field value is 0.000460332 V/m\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#for half wave dipole\n",
+    "#on applying kvl\n",
+    "\n",
+    "Im=0.0768;\n",
+    "Rrad=73;\n",
+    "r=10**4;\n",
+    "Prad=0.5*Rrad*Im**2;#Rrad=73 for half wave dipole\n",
+    "print(\"The radiated power is %g W\"%Prad);\n",
+    "Gd=1.6405#on taking antilog of Gd(in db)\n",
+    "E4=Prad/(4*(math.pi)*r**2);\n",
+    "E3=1.6405*E4;\n",
+    "E2=E3*240*(math.pi);\n",
+    "print(\"E2 = %g\"%E2);\n",
+    "E=math.sqrt(E2);\n",
+    "print(\"The field value is %g V/m\"%E);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.19 Power calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 14,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The length of antenna is 1.5 m\n",
+      "The power radiated is 22812.5 W\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#frequency=100 MHz\n",
+    "\n",
+    "frequency=100*10**6;\n",
+    "lamda=3*10**8/frequency;\n",
+    "leng=lamda/2;\n",
+    "print(\"The length of antenna is %g m\"%leng);\n",
+    "Rrad=73;\n",
+    "Im=25;\n",
+    "Prad=Rrad*0.5*Im**2;\n",
+    "print(\"The power radiated is %g W\"%Prad);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.20 Radiation resistance calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 15,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiation resistance is 53.3333 ohm\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "Im=15;\n",
+    "Prad=6*10**3;\n",
+    "Rrad=Prad/(Im/math.sqrt(2))**2;\n",
+    "print(\"The radiation resistance is %g ohm\"%Rrad);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.21 Directive gain calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 16,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiation efficiency is given by 0.9\n",
+      "The directive gain is 17.6099\n",
+      "The directive gain in db is 12.4576\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Gpmax=n*Gdmax\n",
+    "#N=Rrad/Rrad+Rloss\n",
+    "\n",
+    "Rrad=72;\n",
+    "Rloss=8;\n",
+    "n=Rrad/(Rrad+Rloss);\n",
+    "print(\"The radiation efficiency is given by %g\"%n);\n",
+    "Gpmax=15.8489;#antilog(Gpmax/10);Gpmax=12db\n",
+    "Gdmax=Gpmax/n;\n",
+    "Gdmaxdb=10*math.log10(Gdmax);\n",
+    "print(\"The directive gain is %g\"%Gdmax);\n",
+    "print(\"The directive gain in db is %g\"%Gdmaxdb);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.22 Radiation efficiency calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 17,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The Radiation resistance is 0.49348 ohm\n",
+      "The Power radiated is 3855.31 W\n",
+      "The radiation efficiency is 0.330423\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "dl=1/40;\n",
+    "Im=125;\n",
+    "Rloss=1;\n",
+    "Rrad=80*(math.pi)**2*(dl)**2;\n",
+    "print(\"The Radiation resistance is %g ohm\"%Rrad);\n",
+    "Irms=Im/math.sqrt(2);\n",
+    "Prad=Rrad*(Irms)**2;\n",
+    "print(\"The Power radiated is %g W\"%Prad);\n",
+    "n=Rrad/(Rrad+Rloss);\n",
+    "print(\"The radiation efficiency is %g\"%n);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.23 Efield calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 18,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The Electric field value is 0.194798 V/m\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#|E|^2=sqrt(60*Gd*Prad)/r;\n",
+    "\n",
+    "r=10**4;\n",
+    "Gd=3.1622#antilog(5db/10)\n",
+    "Prad=20*10**3;\n",
+    "E=math.sqrt(60*Gd*Prad)/r;\n",
+    "print(\"The Electric field value is %g V/m\"%E);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.24 Efield calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 20,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The electric field is 0.726865 V/m\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Gd=antilog(12db/10)\n",
+    "\n",
+    "Gd=15.85;\n",
+    "Prad=5*10**3;\n",
+    "r=3*10**3;\n",
+    "E=math.sqrt(60*Gd*Prad)/r;\n",
+    "print(\"The electric field is %g V/m\"%E);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.25 Radiation efficiency calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 21,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The resistance of hertzian dipole is 0.374634 ohm\n",
+      "The radiation efficiency is 0.272558 ohm\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#R=l*sqrt(pi*F*Uo*Sigma)/Sigma*2*pi*r\n",
+    "\n",
+    "L=2;\n",
+    "r=1*10**-3;\n",
+    "f=2*10**6;\n",
+    "u=4*(math.pi)*10**-7;\n",
+    "sig=5.7*10**6;\n",
+    "R=math.sqrt((math.pi)*2*10**6*4*(math.pi)*10**-7/(5.7*10**6))*L/(2*(math.pi)*10**-3);\n",
+    "print(\"The resistance of hertzian dipole is %g ohm\"%R);\n",
+    "dl=2\n",
+    "frequency=2*10**6;\n",
+    "lamda=3*10**8/(frequency);\n",
+    "Rrad=80*(math.pi)**2*(dl/lamda)**2;\n",
+    "n=Rrad/(Rrad+R);\n",
+    "print(\"The radiation efficiency is %g ohm\"%n);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.26 Radiation efficiency calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 22,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiation efficiency is 0.700551\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#half wave dipole\n",
+    "\n",
+    "dl=1/15;#assume lamda=1;\n",
+    "Rloss=1.5;\n",
+    "Rrad=80*(math.pi)**2*(1/15)**2;\n",
+    "n=Rrad/(Rrad+Rloss);\n",
+    "print(\"The radiation efficiency is %g\"%n);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.27 Voltage calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 23,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The voltage induced is 0.08 V\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Leff=Voc/E\n",
+    "\n",
+    "Leff=8;\n",
+    "E=0.01;\n",
+    "Voc=Leff*E;\n",
+    "print(\"The voltage induced is %g V\"%Voc);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.28 Dipole length calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 24,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The length of the half wave dipole is 0.5 m\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Antenna Bandwidth=Operating Frequency/Q;\n",
+    "\n",
+    "Q=30;\n",
+    "f=10*10**6;\n",
+    "f0=f*Q;\n",
+    "c=3*10**8;\n",
+    "lamda=c/f0;\n",
+    "leng=lamda/2;\n",
+    "print(\"The length of the half wave dipole is %g m\"%leng);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.29 effective aperture calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 25,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The wavelength is 0.3 m\n",
+      "The radiation resistance is 7.89568 ohm\n",
+      "The antenna gain is given by 0.9\n",
+      "The effective aperture is 0.010743 m^2\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#part a\n",
+    "c=3*10**8;\n",
+    "f=10**9;\n",
+    "lamda=c/f;\n",
+    "print(\"The wavelength is %g m\"%lamda);\n",
+    "\n",
+    "#part b\n",
+    "dl=3*10**-2;\n",
+    "Rrad=80*(math.pi)**2*(dl/lamda)**2;\n",
+    "print(\"The radiation resistance is %g ohm\"%Rrad);\n",
+    "\n",
+    "#part c\n",
+    "Gdmax=1.5#Gd=1.5sin^2(theta),where theta=90 for short dipole\n",
+    "n=0.6;\n",
+    "Gp=n*Gdmax;\n",
+    "print(\"The antenna gain is given by %g\"%Gp);\n",
+    "\n",
+    "#part d\n",
+    "Ae=1.5*(lamda)**2/(4*(math.pi));\n",
+    "print(\"The effective aperture is %g m^2\"%Ae);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.30 Noise power calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 26,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The power per unit bandwidth is 4.83e-22 W/hz\n",
+      "The available noise power is 1.932e-15 W\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#P=k(Ta+Tr)B\n",
+    "\n",
+    "Ta=15;\n",
+    "Tr=20;\n",
+    "b=4*10**6;\n",
+    "\n",
+    "#part a\n",
+    "k=1.38*10**-23;\n",
+    "Pb=k*(Ta+Tr);\n",
+    "print(\"The power per unit bandwidth is %g W/hz\"%Pb);\n",
+    "\n",
+    "#part b\n",
+    "P=Pb*b;\n",
+    "print(\"The available noise power is %g W\"%P);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.31 Tuning factor calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 27,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The tuning factor Q is 50\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Q=Fo/delf;\n",
+    "\n",
+    "f0=30*10**6;\n",
+    "f=600*10**3;\n",
+    "Q=f0/f;\n",
+    "print(\"The tuning factor Q is %d\"%Q);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.32 Antenna gain calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 28,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The wavelength is 0.015 m\n",
+      "The effective physical aperture is 1.16899 m^2\n",
+      "The antenna gain is 35908.7\n",
+      "The antenna gain in db is 45.552 db\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#part a\n",
+    "c=3*10**8;\n",
+    "frequency=20*10**9;\n",
+    "lamda=c/frequency;\n",
+    "print(\"The wavelength is %g m\"%lamda);\n",
+    "\n",
+    "#part b\n",
+    "#Ae=G*(lamda)^2/4*pi\n",
+    "r=0.61;\n",
+    "Aep=(math.pi)*r**2;\n",
+    "print(\"The effective physical aperture is %g m^2\"%Aep);\n",
+    "Ae=0.55*Aep;\n",
+    "Ga=(Ae*4*(math.pi))/(lamda)**2;\n",
+    "Gdb=10*math.log10(Ga);\n",
+    "print(\"The antenna gain is %g\"%Ga);\n",
+    "print(\"The antenna gain in db is %g db\"%Gdb);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.33 Dipole length calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 29,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The length of half wave dipole is 5 m\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "f=30*10**6;\n",
+    "c=3*10**8;\n",
+    "lamda=c/f;\n",
+    "leng=lamda/2;\n",
+    "print(\"The length of half wave dipole is %d m\"%leng);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.34 Directive gain calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 31,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiation efficiency is 0.9\n",
+      "The directive gain is 17.7778\n",
+      "The directive gain in db is 12.4988 db\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "Rrad=72;\n",
+    "Rloss=8;\n",
+    "Gp=16;\n",
+    "n=Rrad/(Rrad+Rloss);\n",
+    "print(\"The radiation efficiency is %g\"%n);\n",
+    "Gp=16;\n",
+    "Gd=Gp/n;\n",
+    "Gddb=10*math.log10(Gd);\n",
+    "print(\"The directive gain is %g\"%Gd);\n",
+    "print(\"The directive gain in db is %g db\"%Gddb);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.35 Power calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 32,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiated power is 0.000192352 W\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "Gt=1.5;\n",
+    "Gr=1.5;\n",
+    "d=10;\n",
+    "Pt=15;\n",
+    "f=10**9;\n",
+    "c=3*10**8;\n",
+    "lamda=c/f;\n",
+    "Pr=Pt*Gt*Gr*(lamda/(4*(math.pi)*d))**2;\n",
+    "print(\"The radiated power is %g W\"%Pr);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# 2.36 Power calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 33,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The wavelngth is 0.15 m\n",
+      "The transmitted power is 1.57914 W\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "f=2*10**9;\n",
+    "c=3*10**8;\n",
+    "lamda=c/f;\n",
+    "print(\"The wavelngth is %g m\"%lamda);\n",
+    "\n",
+    "#part b\n",
+    "Pr=10**-12;\n",
+    "Gt=200;\n",
+    "Gr=200;\n",
+    "d=3*10**6;\n",
+    "Pt=((4*(math.pi)*d)/lamda)**2*(Pr/(Gt*Gr));\n",
+    "print(\"The transmitted power is %g W\"%Pt);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.37 Gain calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 34,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The wavelength is 3 m\n",
+      "The gain of receiver is 1.63586e+09\n",
+      "The gain of receiver in db is 92.1374 db\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#part a\n",
+    "c=3*10**8;\n",
+    "f=100*10**6;\n",
+    "lamda=c/f;\n",
+    "print(\"The wavelength is %d m\"%lamda);\n",
+    "\n",
+    "#part b\n",
+    "Gt=15.8489#antilog(12/10)\n",
+    "Pt=10**-1;\n",
+    "Pr=10**-9;\n",
+    "d=384.4*10**6;#238857*1609.35\n",
+    "Gr=(((4*(math.pi)*d)/lamda)**2*Pr)/(Pt*Gt);\n",
+    "print(\"The gain of receiver is %g\"%Gr);\n",
+    "Grdb=10*math.log10(Gr);\n",
+    "print(\"The gain of receiver in db is %g db\"%Grdb);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.38 Bandwidth calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 35,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The bandwidth of antenna is 2.000000e+07 Hz\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "Q=15;\n",
+    "lamda=1;\n",
+    "c=3*10**8;\n",
+    "f0=c/lamda;\n",
+    "Bw=f0/Q;\n",
+    "print(\"The bandwidth of antenna is %e Hz\"%Bw);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.39 Directive gain calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 36,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The maximum directive gain is 1.63363\n",
+      "The maximum directive gian in db is 2.13153 db\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Aemax=Gdmax*lamda^2/4*pi;\n",
+    "\n",
+    "Aemax=0.13;#assume lamda=1 for half wave dipole\n",
+    "Gdmax=4*(math.pi)*Aemax;\n",
+    "print(\"The maximum directive gain is %g\"%Gdmax);\n",
+    "Gdmaxdb=10*math.log10(Gdmax);\n",
+    "print(\"The maximum directive gian in db is %g db\"%Gdmaxdb);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.40 Radiated power calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 37,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiated power is 0.007425 W\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "Rloss=1;\n",
+    "Ra=73;\n",
+    "Im=14.166*10**-3;#on applying kvl\n",
+    "Prad=(Im/math.sqrt(2))**2*(Rloss+Ra);\n",
+    "print(\"The radiated power is %g W\"%Prad);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.41 Average power calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 38,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiated power is 50 W\n",
+      "The electric field is given by 0.114676 V/m\n",
+      "The average power is 1.74416e-05 W\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Etheta=n0Im/2pir*cos(pi/2 cos(theta)/sin(theta))\n",
+    "\n",
+    "Pin=100;\n",
+    "n=0.5;\n",
+    "r=500;\n",
+    "Prad=n*Pin;\n",
+    "print(\"The radiated power is %g W\"%Prad);\n",
+    "Rrad=73;#for half wave dipole\n",
+    "Im=math.sqrt((2*Prad)/Rrad);\n",
+    "n0=120*(math.pi);\n",
+    "Etheta=(math.cos((math.pi/2)*math.cos(math.pi/3))/math.sin(math.pi/3))*n0*(Im/(2*(math.pi)*r));\n",
+    "print(\"The electric field is given by %g V/m\"%Etheta);\n",
+    "Pavg=(0.5*(Etheta)**2)/(n0);\n",
+    "print(\"The average power is %g W\"%Pavg);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.42 Radiation Power calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 39,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiated power is 2.31481e-05 W\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "Pt=15\n",
+    "Aet=2.5;\n",
+    "Aer=0.5;\n",
+    "d=15*10**3;\n",
+    "f=5*10**9;\n",
+    "c=3*10**8;\n",
+    "lamda=c/f;\n",
+    "Pr=(Pt*Aet*Aer)/((d)**2*(lamda)**2);\n",
+    "print(\"The radiated power is %g W\"%Pr);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.43 Directive gain calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 40,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The maximum directive gain is 10\n",
+      "The maximum directive gain in db is 10 db\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "n=10;\n",
+    "d=0.25;\n",
+    "lamda=1;#assume\n",
+    "Gdmax=4*((n*d)/lamda);\n",
+    "print(\"The maximum directive gain is %g\"%Gdmax);\n",
+    "Gdmaxdb=10*math.log10(Gdmax);\n",
+    "print(\"The maximum directive gain in db is %g db\"%Gdmaxdb);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.44 Radiation efficiency calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 41,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiation efficiency is 0.866667\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "Rrad=65;\n",
+    "Rloss=10;\n",
+    "n=Rrad/(Rrad+Rloss);\n",
+    "print(\"The radiation efficiency is %g\"%n);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.45 Effective aperture calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 42,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The effective aperture is 0.010743 m^2\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Aem=Gdmax*lamda^2/4*pi;\n",
+    "\n",
+    "Gdmax=1.5;#for half wave dipole\n",
+    "f=10**9;\n",
+    "c=3*10**8;\n",
+    "lamda=c/f;\n",
+    "Aem=(Gdmax*(lamda)**2)/(4*(math.pi));\n",
+    "print(\"The effective aperture is %g m^2\"%Aem);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.46 FBR ratio calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 43,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The front to back ratio is 6\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "Pdes=3*10**3;\n",
+    "Popp=500;\n",
+    "FBR=Pdes/Popp;\n",
+    "print(\"The front to back ratio is %d\"%FBR);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 2.47 Radiation resistance calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 44,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiation resistance is 0.315827 ohm\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "dl=1/50;\n",
+    "Rr=80*(math.pi)**2*(dl)**2;\n",
+    "print(\"The radiation resistance is %g ohm\"%Rr);"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.5.2"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 1
+}
diff --git a/Antenna_and_Wave_Propogation_by_U._A._Bakshi_and_A._V._Bakshi/Chapter3Loop_and_Helical_Antenna.ipynb b/Antenna_and_Wave_Propogation_by_U._A._Bakshi_and_A._V._Bakshi/Chapter3Loop_and_Helical_Antenna.ipynb
new file mode 100644
index 00000000..e85d677a
--- /dev/null
+++ b/Antenna_and_Wave_Propogation_by_U._A._Bakshi_and_A._V._Bakshi/Chapter3Loop_and_Helical_Antenna.ipynb
@@ -0,0 +1,185 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 3 Loop and Helical Antenna"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 3.1 Directive gain calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "metadata": {
+    "collapsed": false,
+    "scrolled": true
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The directive gain is 63.723\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#tan(alpha)=s/c;\n",
+    "#helical antenna Gdmax=15NSC^2/lamda^3\n",
+    "c=1;\n",
+    "n=20;\n",
+    "lamda=1;\n",
+    "s=math.tan(0.2093)*1;  #12*math.pi/180 radians\n",
+    "Gdmax=(15*n*s*(c)**2)/(lamda)**3;\n",
+    "print(\"The directive gain is %.3f\"%Gdmax)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 3.2 HPBW calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 8,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The wavelength is 0.1 m\n",
+      "The directive gain is 900\n",
+      "The half power beamwidth is 21.2289 degree\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#helical antenna\n",
+    "#part a\n",
+    "c=3*10**8;\n",
+    "f=3*10**9;\n",
+    "lamda=c/f;\n",
+    "print(\"The wavelength is %g m\"%lamda);\n",
+    "\n",
+    "#part b\n",
+    "n=20;\n",
+    "s=0.03;\n",
+    "c=0.1;\n",
+    "Gdmax=(15*20*0.3*(0.1)**2)/(0.1)**3;\n",
+    "print(\"The directive gain is %g\"%Gdmax);\n",
+    "\n",
+    "#part c\n",
+    "HPBW=math.sqrt((0.1)**3/(20*0.03))*520;\n",
+    "print(\"The half power beamwidth is %g degree\"%HPBW)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 3.3 Radiation resistance calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 9,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiation resistance is 30.7932 ohm\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#loop antenna\n",
+    "r=10;\n",
+    "lamda=100;\n",
+    "A=(math.pi)*r**2;\n",
+    "Rr=31200*(A/lamda**2)**2;\n",
+    "print(\"The radiation resistance is %g ohm\"%Rr);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 3.4 Radiation Resisitance calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 10,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiation resistance is 3.12 ohm\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#loop antenna\n",
+    "l=1;\n",
+    "b=1;\n",
+    "A=l*b;\n",
+    "lamda=100;\n",
+    "Rrad=31200*(A/lamda**2);\n",
+    "print(\"The radiation resistance is %g ohm\"%Rrad);"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.5.2"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 1
+}
diff --git a/Antenna_and_Wave_Propogation_by_U._A._Bakshi_and_A._V._Bakshi/Chapter4Antenna_Arrays.ipynb b/Antenna_and_Wave_Propogation_by_U._A._Bakshi_and_A._V._Bakshi/Chapter4Antenna_Arrays.ipynb
new file mode 100644
index 00000000..2e5e087d
--- /dev/null
+++ b/Antenna_and_Wave_Propogation_by_U._A._Bakshi_and_A._V._Bakshi/Chapter4Antenna_Arrays.ipynb
@@ -0,0 +1,607 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 4 Antenna Arrays"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 4.1 HPBW calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The Beam Width First Null is 114.592 degree\n",
+      "The half power beam width is 57.2958 degree\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#D=2(L/lamda)\n",
+    "#broadside array\n",
+    "L=1;\n",
+    "Lamda=1;#assume\n",
+    "BWFN=2 *180/(math.pi); #2/(L/lamda)\n",
+    "print(\"The Beam Width First Null is %g degree\"%BWFN);\n",
+    "HPBW=BWFN/2;\n",
+    "print(\"The half power beam width is %g degree\"%HPBW);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 4.2 BWFN calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The Beam Width First Null is 54.023 degree\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#end fire array\n",
+    "#D=4(L/lamda)\n",
+    "#BWFN=2sqrt(2m/(L/lamda))\n",
+    "lamda=1;\n",
+    "D=36;\n",
+    "L=D/4;\n",
+    "m=1;\n",
+    "BWFN=114.6*math.sqrt(2*m/L);\n",
+    "print(\"The Beam Width First Null is %g degree\"%BWFN);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 4.3 Maxima Minima calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The positions of maxima are 1.5708,0,3.14159 radians\n",
+      "The positions of minima are 1.0472,1.0472 radians\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#2 element array\n",
+    "#part a\n",
+    "max1=math.acos(0);\n",
+    "max2=math.acos(1);\n",
+    "max3=math.acos(-1);\n",
+    "print(\"The positions of maxima are %g,%d,%g radians\"%(max1,max2,max3));\n",
+    "\n",
+    "#part b\n",
+    "#minima\n",
+    "min1=math.acos(0.5);\n",
+    "min2=math.acos(0.5);\n",
+    "print(\"The positions of minima are %g,%g radians\"%(min1,min2));"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 4.4 Radiation Pattern calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The only position of maximum radiation is 0 radians\n",
+      "The position of minimum radiation pattern is 3.14159 radians\n",
+      "Et 0.6203340637620398\n",
+      "Hence as the radiation pattern suggest that antenna is unidirectional antenna\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#2 element array\n",
+    "max1=math.acos(1);\n",
+    "print(\"The only position of maximum radiation is %d radians\"%max1);\n",
+    "min1=math.acos(-1);\n",
+    "print(\"The position of minimum radiation pattern is %g radians\"%min1);\n",
+    "phi=180;#assume phi=180 degree;\n",
+    "Et=2*math.cos(((math.pi/4)*math.cos(phi))-(math.pi/4));\n",
+    "print('Et',Et);\n",
+    "print(\"Hence as the radiation pattern suggest that antenna is unidirectional antenna\");"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 4.5 Null Calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The direction of nulls are 1.31812 1.0472 0.722734 radians\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#broadside array\n",
+    "#part a\n",
+    "n=8;\n",
+    "m1=1;\n",
+    "d=0.5;\n",
+    "lamda=1;\n",
+    "ph1=math.acos((m1*lamda)/(n*d));\n",
+    "m2=2; \n",
+    "ph2=math.acos((m2*lamda)/(n*d));\n",
+    "m3=3;\n",
+    "ph3=math.acos((m3*lamda)/(n*d));\n",
+    "print(\"The direction of nulls are %g %g %g radians\"%(ph1,ph2,ph3));"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 4.6 Lobe calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 8,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The minor lobes values are 1.1864 0.895665 0.505361\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#taking values from previous problems \n",
+    "#broadside array\n",
+    "m1=1;\n",
+    "n=8;\n",
+    "d=0.5;\n",
+    "lamda=1;\n",
+    "ph1=math.acos(lamda*(2*m1+1)/(2*n*d));\n",
+    "m2=2;\n",
+    "ph2=math.acos(lamda*(2*m2+1)/(2*n*d));\n",
+    "m3=3;\n",
+    "ph3=math.acos(lamda*(2*m3+1)/(2*n*d));\n",
+    "print(\"The minor lobes values are %g %g %g\"%(ph1,ph2,ph3));"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 4.7 BWFN calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 9,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The radiated power is 18.25 W\n",
+      "The length is 2 m\n",
+      "The Beam width first null is 0.1 radians\n",
+      "The half power beam width is 0.05 radians\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#broadside array\n",
+    "n=4;\n",
+    "lamda=0.1\n",
+    "d=0.5\n",
+    "i=0.25\n",
+    "Rrad=73;\n",
+    "\n",
+    "#part a\n",
+    "Prad=n*(i**2*Rrad);\n",
+    "print(\"The radiated power is %g W\"%Prad);\n",
+    "\n",
+    "#part b\n",
+    "L=n*d;\n",
+    "print(\"The length is %d m\"%L);\n",
+    "BWFN=2*lamda/L;\n",
+    "HPBW=BWFN/2;\n",
+    "print(\"The Beam width first null is %g radians\"%BWFN);\n",
+    "print(\"The half power beam width is %g radians\"%HPBW);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 4.8 Dmin calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 10,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The minimum distance between array is 0.250554 m\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#broadside array\n",
+    "Gdmax=5.01108; #antilog[7/10]\n",
+    "n=10;\n",
+    "lamda=1;\n",
+    "d=Gdmax/(20*lamda);\n",
+    "print(\"The minimum distance between array is %g m\"%d);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 4.9 Gain calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 12,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "In Case of Broadside array\n",
+      "The directive gain is 4\n",
+      "The directive gain in db is 6.0206 db\n",
+      "\n",
+      "In case of End fire array\n",
+      "The directive gain is 8\n",
+      "The directive gain in db is 9.0309 db\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#broadside array\n",
+    "n=8;\n",
+    "d=0.25;\n",
+    "lamda=1;\n",
+    "\n",
+    "#part a\n",
+    "Gdmax=(2*n*d)/lamda;\n",
+    "Gdmaxdb=10*math.log10(Gdmax);\n",
+    "print(\"In Case of Broadside array\")\n",
+    "print(\"The directive gain is %g\"%Gdmax);\n",
+    "print(\"The directive gain in db is %g db\"%Gdmaxdb);\n",
+    "\n",
+    "#part b\n",
+    "#end fire array\n",
+    "Gdmax1=(4*n*d)/lamda;\n",
+    "Gdmaxdb1=10*math.log10(Gdmax1);\n",
+    "print(\"\\nIn case of End fire array\");\n",
+    "print(\"The directive gain is %g\"%Gdmax1);\n",
+    "print(\"The directive gain in db is %g db\"%Gdmaxdb1);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 4.10 BWFN calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 14,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The length is 7.5 m\n",
+      "The length is 3.75 m\n",
+      "The BWFN is 83.692 degree\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#broadside array\n",
+    "Gdmax=15;\n",
+    "L=Gdmax/2;\n",
+    "print(\"The length is %g m\"%L);\n",
+    "\n",
+    "#endfire array\n",
+    "L1=Gdmax/4;\n",
+    "print(\"The length is %g m\"%L1);\n",
+    "BWFN=114.6*math.sqrt(2/L1);\n",
+    "print(\"The BWFN is %g degree\"%BWFN);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 4.11 Directivity calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 15,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The directivity is 17.89\n",
+      "The directivity in db is 12.5261 db\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Hansen-Woodyard end fire array\n",
+    "n=10;\n",
+    "d=0.25;\n",
+    "L=n*d;\n",
+    "D=1.789*4*L;\n",
+    "Ddb=10*math.log10(D);\n",
+    "print(\"The directivity is %g\"%D);\n",
+    "print(\"The directivity in db is %g db\"%Ddb);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 4.12 Effective Aperture calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 16,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The HPBW is 41.846 degree\n",
+      "The directivity is 15\n",
+      "The directivity in db is 11.7609 db\n",
+      "The beam solid angle is 0.837758 sr\n",
+      "The effective aperture is 1.19366 m^2\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#end fire array\n",
+    "n=16;\n",
+    "d=0.25;\n",
+    "L=(n-1)*d;\n",
+    "m=1;\n",
+    "\n",
+    "#part a\n",
+    "HPBW=57.3*math.sqrt((2*m)/L);\n",
+    "print(\"The HPBW is %g degree\"%HPBW);\n",
+    "\n",
+    "#part b\n",
+    "D=4*L;\n",
+    "Ddb=10*math.log10(D);\n",
+    "print(\"The directivity is %d\"%D);\n",
+    "print(\"The directivity in db is %g db\"%Ddb);\n",
+    "\n",
+    "#part c\n",
+    "A=4*(math.pi)/D;\n",
+    "print(\"The beam solid angle is %g sr\"%A);\n",
+    "\n",
+    "#part d\n",
+    "lamda=1;\n",
+    "Ae=D*lamda**2/(4*(math.pi));\n",
+    "print(\"The effective aperture is %g m^2\"%Ae);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 4.13 Directive Gain Calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 18,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The directive gain is 10\n",
+      "The directive gain in db is 10 db\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#end fire array\n",
+    "n=10;\n",
+    "d=0.25;\n",
+    "lamda=1;#assume\n",
+    "Gdmax=4*n*d;\n",
+    "Gdmaxdb=10*math.log10(Gdmax);\n",
+    "print(\"The directive gain is %d\"%Gdmax);\n",
+    "print(\"The directive gain in db is %d db\"%Gdmaxdb);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 4.14 Directivity calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 19,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The directivity is 50\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "n=50;\n",
+    "d=0.5;\n",
+    "lamda=1;#assume\n",
+    "L=n*d;\n",
+    "D=2*(L/lamda);\n",
+    "print(\"The directivity is %g\"%D);"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.5.2"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 1
+}
diff --git a/Antenna_and_Wave_Propogation_by_U._A._Bakshi_and_A._V._Bakshi/Chapter6Aperture_and_Lens_Antenna.ipynb b/Antenna_and_Wave_Propogation_by_U._A._Bakshi_and_A._V._Bakshi/Chapter6Aperture_and_Lens_Antenna.ipynb
new file mode 100644
index 00000000..85cca3f8
--- /dev/null
+++ b/Antenna_and_Wave_Propogation_by_U._A._Bakshi_and_A._V._Bakshi/Chapter6Aperture_and_Lens_Antenna.ipynb
@@ -0,0 +1,126 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 6 Aperture and Lens Antenna"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 6.1 Directive gain calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The length is 62.5 m\n",
+      "The angle ThetaE is 9.14784 degree\n",
+      "The angle ThetaH is 12.5216 degree\n",
+      "The H plane aperture is 13.7136\n",
+      "\n",
+      "\n",
+      "The HPBWE is 5.6 degree\n",
+      "The HPBWH is 4.88567 degree\n",
+      "The Directive gain in db is 30.1221 db\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#horn antenna\n",
+    "Ae=10;\n",
+    "del_a=0.2;\n",
+    "p=Ae**2/(8*del_a);\n",
+    "del1=0.375;\n",
+    "Thetae=2*math.atan((Ae/(2*p)))*180/(math.pi); #flare angle\n",
+    "Thetah=2*math.acos(p/(p+del1))*180/(math.pi);\n",
+    "Ah=2*p*math.tan(((Thetah*(math.pi)/180)/2));\n",
+    "print(\"The length is %g m\"%p);\n",
+    "print(\"The angle ThetaE is %g degree\"%Thetae);\n",
+    "print(\"The angle ThetaH is %g degree\"%Thetah);\n",
+    "print(\"The H plane aperture is %g\"%Ah);\n",
+    "HPBWH=67/Ah;\n",
+    "HPBWE=56/Ae;\n",
+    "Ddb=10*math.log10((7.5*Ae*Ah));\n",
+    "print('\\n')\n",
+    "print(\"The HPBWE is %g degree\"%HPBWE);\n",
+    "print(\"The HPBWH is %g degree\"%HPBWH);\n",
+    "print(\"The Directive gain in db is %g db\"%Ddb);   "
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 6.2 Effective aperture calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The diameter d is 1.4 m\n",
+      "The effective aperture is 1.53938 m^2\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#parabolic reflector antenna\n",
+    "BWFN=10;\n",
+    "f=3*10**9;\n",
+    "c=3*10**8;\n",
+    "lamda=c/f;\n",
+    "d=140*lamda/(BWFN);\n",
+    "print(\"The diameter d is %g m\"%d);\n",
+    "#For circular parabolidal antenna\n",
+    "Ae=((math.pi)*(d**2))/4;\n",
+    "print(\"The effective aperture is %g m^2\"%Ae);"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.5.2"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 1
+}
diff --git a/Antenna_and_Wave_Propogation_by_U._A._Bakshi_and_A._V._Bakshi/Chapter7Propagation_of_Radio_Waves.ipynb b/Antenna_and_Wave_Propogation_by_U._A._Bakshi_and_A._V._Bakshi/Chapter7Propagation_of_Radio_Waves.ipynb
new file mode 100644
index 00000000..1b7b1b68
--- /dev/null
+++ b/Antenna_and_Wave_Propogation_by_U._A._Bakshi_and_A._V._Bakshi/Chapter7Propagation_of_Radio_Waves.ipynb
@@ -0,0 +1,632 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 7 Propagation of Radio Waves"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.1 Frequency calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The maximum stable frequency is 1.76086e+07 Hz\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "fcr=11*10**6;\n",
+    "D=1000;\n",
+    "h=400;\n",
+    "fmuf=fcr*math.sqrt(1+(D/(2*h))**2);\n",
+    "print(\"The maximum stable frequency is %g Hz\"%fmuf);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.2 Usable frequency calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The critical frequency is 2.84605e+06 Hz\n",
+      "The maximum usable frequency is 3.0287e+06 Hz\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "Nmax=10**11;\n",
+    "phi=(math.pi)/9;\n",
+    "fcr=math.sqrt(81*Nmax);\n",
+    "print(\"The critical frequency is %g Hz\"%fcr);\n",
+    "fmuf=fcr*(1/math.cos(phi));\n",
+    "print(\"The maximum usable frequency is %g Hz\"%fmuf);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.3 Critical frequency calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The critical frequency is 6.00115e+06 Hz\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "D=2000;\n",
+    "h=200;\n",
+    "fmuf=30.6*10**6;\n",
+    "fcr=fmuf/math.sqrt(1+(D/(2*h))**2);\n",
+    "print(\"The critical frequency is %g Hz\"%fcr);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.4 Skip distance calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The Nmax value is 2.34568e+11 /m^3\n",
+      "The critical frequency is 4.3589e+06 Hz\n",
+      "The skip distance is 1.65179e+06 m\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "n=0.9;\n",
+    "fmuf=10*10**6;\n",
+    "f=10*10**6;\n",
+    "h=400*10**3;\n",
+    "Nmax=(1-n**2)*f**2/81;\n",
+    "print(\"The Nmax value is %g /m^3\"%Nmax);\n",
+    "fcr=math.sqrt(81*Nmax);\n",
+    "print(\"The critical frequency is %g Hz\"%fcr);\n",
+    "Dskip=2*h*math.sqrt((fmuf/fcr)**2-1);\n",
+    "print(\"The skip distance is %g m\"%Dskip);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.5 Efield calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The wavelength is 250 m\n",
+      "The electric field is 0.101788 V/m\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "ht=150;\n",
+    "hr=2;\n",
+    "Is=9;\n",
+    "d=40*10**3;\n",
+    "f=1.2*10**6;\n",
+    "c=3*10**8;\n",
+    "lamda=c/f;\n",
+    "print(\"The wavelength is %d m\"%lamda);\n",
+    "E=120*(math.pi)*ht*hr*Is/(lamda*d);\n",
+    "print(\"The electric field is %g V/m\"%E);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.6 Transmission height calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The height of transmission is 2.98243e+07 m\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "dmax=45*10**3;\n",
+    "ht=(dmax/8.24)**2; #dmax=4.12[sqrt(ht)+sqrt(hr)];ht=hr;\n",
+    "print(\"The height of transmission is %g m\"%ht);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.7 Nmax calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": true
+   },
+   "outputs": [],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "fcre=2.5*10**6;\n",
+    "fcrf=8.5*10**6;\n",
+    "Nmaxe=(fcre)**2/81;\n",
+    "Nmaxf=(fcrf)**2/81;\n",
+    "print(\"The Nmax for e layer is %g /m^3\"%Nmaxe);\n",
+    "print(\"The Nmax for f layer is %g /m^3\"%Nmaxf);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.8 Critical freq calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The critical frequencies are 14.2302Hz 16.8375Hz 11.0227Hz\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "Nmaxf1=2.5;\n",
+    "Nmaxf2=3.5;\n",
+    "Nmaxf3=1.5;#10^6*10^-6=1;\n",
+    "fcr1=math.sqrt(81*Nmaxf1);\n",
+    "fcr2=math.sqrt(81*Nmaxf2);\n",
+    "fcr3=math.sqrt(81*Nmaxf3);\n",
+    "print(\"The critical frequencies are %gHz %gHz %gHz\"%(fcr1,fcr2,fcr3));"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.9 Electron Density calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The Nmax values are 2.5e+11 m^3 2.77778e+10 m^3\n",
+      "The change in electron density is 2.22222e+11 m^3\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "fcr1=4.5*10**6;\n",
+    "fcr2=1.5*10**6;\n",
+    "Nmax1=(fcr1/9)**2;\n",
+    "Nmax2=(fcr2/9)**2;\n",
+    "print(\"The Nmax values are %g m^3 %g m^3\"%(Nmax1,Nmax2));\n",
+    "Nmax=Nmax1-Nmax2;\n",
+    "print(\"The change in electron density is %g m^3\"%Nmax);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.10 Frequency calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The frequency is 2.078461e+05 Hz\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "#Note:10^6 is the power and not 10^-6 as mentioned in book\n",
+    "n=0.5;\n",
+    "N=400*10**6;\n",
+    "f=math.sqrt((81*N)/(1-n**2));\n",
+    "print(\"The frequency is %e Hz\"%f);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.11 Critical freq calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 8,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The critical frequency is 1.200084e+07 Hz\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "D=1500;\n",
+    "h=250;\n",
+    "fmuf=37.95*10**6;\n",
+    "fcr=fmuf/math.sqrt(1+(D/(2*h))**2);\n",
+    "print(\"The critical frequency is %e Hz\"%fcr);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.12 Usable freq calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 9,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The maximum usable frequency is 3.16475e+07 Hz\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "D=2500;\n",
+    "h=200;\n",
+    "fcr=5*10**6;\n",
+    "fmuf=fcr*math.sqrt(1+(D/(2*h))**2);\n",
+    "print(\"The maximum usable frequency is %g Hz\"%fmuf);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.13 virtual height calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 10,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The virtual height is given by 750000 m\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "T=5*10**-3;\n",
+    "c=3*10**8;\n",
+    "h=c*(T/2);\n",
+    "print(\"The virtual height is given by %g m\"%h);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.14 LOS calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 11,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The line of sight distance is 46.6572 m\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "ht=40;\n",
+    "hr=25;\n",
+    "f=90*10**6;\n",
+    "p=35;\n",
+    "LOS=4.12*(math.sqrt(ht)+math.sqrt(hr));\n",
+    "print(\"The line of sight distance is %g m\"%LOS);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.15 critical freq calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 12,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The critical frequency is 1.01025e+07 Hz\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "Nmax=1.26*10**12;\n",
+    "fcr=math.sqrt(81*Nmax);\n",
+    "print(\"The critical frequency is %g Hz\"%fcr)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.16 critical freq calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 13,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The critical frequency is 1.0022e+07 Hz\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "Nmax=1.24*10**12;\n",
+    "fcr=math.sqrt(81*Nmax);\n",
+    "print(\"The critical frequency is %g Hz\"%fcr);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.17 usable freq calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 14,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The maximum usable frequency is 6.7082e+06 Hz\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "fcr=6*10**6;\n",
+    "D=200*10**3;\n",
+    "h=200*10**3;\n",
+    "fmuf=fcr*math.sqrt(1+(D/(2*h))**2);\n",
+    "print(\"The maximum usable frequency is %g Hz\"%fmuf);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 7.18 Range calculation"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 15,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The maximum range is 24.1419 miles\n"
+     ]
+    }
+   ],
+   "source": [
+    "from __future__ import division\n",
+    "import math\n",
+    "\n",
+    "ht=100;\n",
+    "hr=50;\n",
+    "d=1.4142*(math.sqrt(ht)+math.sqrt(hr));\n",
+    "print(\"The maximum range is %g miles\"%d);"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.5.2"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 1
+}
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter14KineticsofaParticleWorkandEnergy.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter14KineticsofaParticleWorkandEnergy.ipynb
index 2fcc32fb..2fcc32fb 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter14KineticsofaParticleWorkandEnergy.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter14KineticsofaParticleWorkandEnergy.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_1.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_1.ipynb
index 62d27f1f..62d27f1f 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_1.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_1.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_10_Moments.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_10_Moments.ipynb
index c3e6cf59..c3e6cf59 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_10_Moments.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_10_Moments.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_10_Moments_of_Inertia.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_10_Moments_of_Inertia.ipynb
index c3e6cf59..89f93cee 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_10_Moments_of_Inertia.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_10_Moments_of_Inertia.ipynb
@@ -170,7 +170,7 @@
    ],
    "source": [
     "# Ex 10.6\n",
-    "import math\n",
+    "\n",
     "from __future__ import division\n",
     "\n",
     "# Calculation\n",
@@ -298,6 +298,7 @@
    "source": [
     "# Ex 10.11\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "rho = 8000  #[kg meter**(2)]\n",
@@ -338,7 +339,7 @@
    ],
    "source": [
     "# Ex 10.12\n",
-    "import math\n",
+    "\n",
     "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
@@ -372,21 +373,21 @@
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_11_.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_11_.ipynb
index 3ee3ef32..3ee3ef32 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_11_.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_11_.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_11__Virtual_Work.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_11__Virtual_Work.ipynb
index 3ee3ef32..a978e00c 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_11__Virtual_Work.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_11__Virtual_Work.ipynb
@@ -68,6 +68,7 @@
     "# Ex 11.3\n",
     "import math\n",
     "import numpy as np\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "theta = 45  #[Degrees]\n",
@@ -192,21 +193,21 @@
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_12_Kinematics_of.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_12_Kinematics_of.ipynb
index 59332347..59332347 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_12_Kinematics_of.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_12_Kinematics_of.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_12_Kinematics_of_a_Particle.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_12_Kinematics_of_a_Particle.ipynb
index 59332347..89bf4495 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_12_Kinematics_of_a_Particle.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_12_Kinematics_of_a_Particle.ipynb
@@ -163,6 +163,8 @@
    "source": [
     "# Ex 12.4\n",
     "from scipy import integrate\n",
+    "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "vB = round(2*(0.2**(2)-0.01)**(0.5)*1000,1)  #[millimeter per second]\n",
@@ -200,6 +202,7 @@
    ],
    "source": [
     "# Ex 12.5\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# ds = vdt\n",
@@ -642,6 +645,7 @@
    "source": [
     "# Ex 12.10\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Position\n",
@@ -828,6 +832,8 @@
    ],
    "source": [
     "# Ex 12.14\n",
+    "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Velocity\n",
@@ -871,6 +877,8 @@
    ],
    "source": [
     "# Ex 12.15\n",
+    "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Let t be time needed for acceleration to reach 3 m/s**(2)\n",
@@ -951,6 +959,7 @@
    "source": [
     "# Ex 12.18\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "vr = 200*1  #[millimeter per second]\n",
@@ -1143,6 +1152,7 @@
    ],
    "source": [
     "# Ex 12.23\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "vB = -2/4\n",
@@ -1177,6 +1187,7 @@
    "source": [
     "# Ex 12.24\n",
     "from __future__ import division\n",
+    "import math\n",
     "\n",
     "# Variable Declaration\n",
     "vA = 0.5  #[meter per second]\n",
@@ -1222,6 +1233,7 @@
    "source": [
     "# Ex 12.25\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation Solution 1 Vector Analysis\n",
     "vTA_x = round(60-45*math.cos(math.pi*45/180),1)  #[kilometer per hr]\n",
@@ -1273,6 +1285,7 @@
    "source": [
     "# Ex 12.26\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "rho = 400  #[kilometers]\n",
@@ -1321,6 +1334,7 @@
    "source": [
     "# Ex 12.27\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "vA = 18  #[meter per second]\n",
@@ -1360,21 +1374,21 @@
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_13_Kinetics_of_a_Particle_Force.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_13_Kinetics_of_a_Particle_Force.ipynb
index ada4b114..ada4b114 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_13_Kinetics_of_a_Particle_Force.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_13_Kinetics_of_a_Particle_Force.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_13_Kinetics_of_a_Particle_Force_and_Acceleration.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_13_Kinetics_of_a_Particle_Force_and_Acceleration.ipynb
index ada4b114..81d0b746 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_13_Kinetics_of_a_Particle_Force_and_Acceleration.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_13_Kinetics_of_a_Particle_Force_and_Acceleration.ipynb
@@ -33,6 +33,7 @@
     "# Ex 13.1\n",
     "import numpy as np\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "uk = 0.3\n",
@@ -164,6 +165,7 @@
     "# Ex 13.4\n",
     "import numpy as np\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "k = 3  #[Newtons per meter]\n",
@@ -250,6 +252,7 @@
    "source": [
     "# Ex 13.7\n",
     "from __future__ import division\n",
+    "import math\n",
     "\n",
     "# Variable Declaration\n",
     "uk = 0.1\n",
@@ -333,6 +336,8 @@
    ],
    "source": [
     "# Ex 13.9\n",
+    "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "thetamax = round(math.degrees((9.81+1)/((19.62*0.5/2)+9.81)),1)  #[Degrees]\n",
@@ -411,7 +416,7 @@
     "# Ex 13.11\n",
     "import numpy as np\n",
     "import math\n",
-    "\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "theta = 60  #[Degrees]\n",
@@ -482,21 +487,21 @@
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_14_Kinetics_of_a_Particle_Work_and_Energy_.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_14_Kinetics_of_a_Particle_Work_and_Energy_.ipynb
index 2fcc32fb..fddb008e 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_14_Kinetics_of_a_Particle_Work_and_Energy_.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_14_Kinetics_of_a_Particle_Work_and_Energy_.ipynb
@@ -191,6 +191,7 @@
    "source": [
     "# Ex 14.5\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "thetamax = round(math.degrees(math.acos((9.81+1)/(4.905+9.81))),1)  #[Degrees]\n",
@@ -300,6 +301,7 @@
    "source": [
     "# Ex 14.9\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Using Principle of Conservation of Energy\n",
@@ -406,21 +408,21 @@
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_15_Kinetics_of_a_Particle_Impulse.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_15_Kinetics_of_a_Particle_Impulse.ipynb
index 1157bdc9..1157bdc9 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_15_Kinetics_of_a_Particle_Impulse.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_15_Kinetics_of_a_Particle_Impulse.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_15_Kinetics_of_a_Particle_Impulse_and_Momentum.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_15_Kinetics_of_a_Particle_Impulse_and_Momentum.ipynb
index 1157bdc9..305cb41e 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_15_Kinetics_of_a_Particle_Impulse_and_Momentum.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_15_Kinetics_of_a_Particle_Impulse_and_Momentum.ipynb
@@ -17,9 +17,7 @@
   {
    "cell_type": "code",
    "execution_count": 1,
-   "metadata": {
-    "collapsed": false
-   },
+   "metadata": {},
    "outputs": [
     {
      "name": "stdout",
@@ -33,6 +31,7 @@
    "source": [
     "# Ex 15.1\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "ws = 100  #[kilogram]\n",
@@ -58,9 +57,7 @@
   {
    "cell_type": "code",
    "execution_count": 3,
-   "metadata": {
-    "collapsed": false
-   },
+   "metadata": {},
    "outputs": [
     {
      "name": "stdout",
@@ -74,6 +71,7 @@
    "source": [
     "# Ex 15.2\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Using +ΣFy = 0\n",
@@ -95,9 +93,7 @@
   {
    "cell_type": "code",
    "execution_count": 12,
-   "metadata": {
-    "collapsed": false
-   },
+   "metadata": {},
    "outputs": [
     {
      "name": "stdout",
@@ -135,9 +131,7 @@
   {
    "cell_type": "code",
    "execution_count": 14,
-   "metadata": {
-    "collapsed": false
-   },
+   "metadata": {},
    "outputs": [
     {
      "name": "stdout",
@@ -150,6 +144,7 @@
    ],
    "source": [
     "# Ex 15.4\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Part(a)\n",
@@ -172,9 +167,7 @@
   {
    "cell_type": "code",
    "execution_count": 17,
-   "metadata": {
-    "collapsed": false
-   },
+   "metadata": {},
    "outputs": [
     {
      "name": "stdout",
@@ -187,6 +180,7 @@
    ],
    "source": [
     "# Ex 15.5\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Part(a)\n",
@@ -209,9 +203,7 @@
   {
    "cell_type": "code",
    "execution_count": 20,
-   "metadata": {
-    "collapsed": false
-   },
+   "metadata": {},
    "outputs": [
     {
      "name": "stdout",
@@ -223,6 +215,7 @@
    ],
    "source": [
     "# Ex 15.6\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "vT2 = round((350*10**(3)*3)/(350*10**(3)+50*10**(3)),2)  #[meters per second]\n",
@@ -241,9 +234,7 @@
   {
    "cell_type": "code",
    "execution_count": 5,
-   "metadata": {
-    "collapsed": false
-   },
+   "metadata": {},
    "outputs": [
     {
      "name": "stdout",
@@ -284,9 +275,7 @@
   {
    "cell_type": "code",
    "execution_count": 24,
-   "metadata": {
-    "collapsed": false
-   },
+   "metadata": {},
    "outputs": [
     {
      "name": "stdout",
@@ -300,6 +289,7 @@
     "# Ex 15.9\n",
     "import numpy as np\n",
     "from __future__ import division\n",
+    "import math\n",
     "\n",
     "# Calculation\n",
     "# Using conservation of energy\n",
@@ -326,9 +316,7 @@
   {
    "cell_type": "code",
    "execution_count": 6,
-   "metadata": {
-    "collapsed": false
-   },
+   "metadata": {},
    "outputs": [
     {
      "name": "stdout",
@@ -371,10 +359,8 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 32,
-   "metadata": {
-    "collapsed": false
-   },
+   "execution_count": 1,
+   "metadata": {},
    "outputs": [
     {
      "name": "stdout",
@@ -391,7 +377,7 @@
     "# Ex 15.11\n",
     "import numpy as np\n",
     "import math\n",
-    "\n",
+    "from __future__ import division\n",
     "# Calculation\n",
     "vAx1 = round(3*math.cos(math.pi*30/180),2)\n",
     "vAy1 = round(3*math.sin(math.pi*30/180),2)\n",
@@ -424,9 +410,7 @@
   {
    "cell_type": "code",
    "execution_count": 7,
-   "metadata": {
-    "collapsed": false
-   },
+   "metadata": {},
    "outputs": [
     {
      "name": "stdout",
@@ -461,9 +445,7 @@
   {
    "cell_type": "code",
    "execution_count": 35,
-   "metadata": {
-    "collapsed": false
-   },
+   "metadata": {},
    "outputs": [
     {
      "name": "stdout",
@@ -475,6 +457,8 @@
    ],
    "source": [
     "# Ex 15.14\n",
+    "from __future__ import division\n",
+    "import math\n",
     "\n",
     "# Variable Declaration\n",
     "v1 = 1  #[meters per second]\n",
@@ -504,9 +488,7 @@
   {
    "cell_type": "code",
    "execution_count": 38,
-   "metadata": {
-    "collapsed": false
-   },
+   "metadata": {},
    "outputs": [
     {
      "name": "stdout",
@@ -548,7 +530,7 @@
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 2",
    "language": "python",
    "name": "python2"
   },
@@ -562,7 +544,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "version": "2.7.13"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_16_Planar_Kinematics_of_a.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_16_Planar_Kinematics_of_a.ipynb
index 677b13e4..677b13e4 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_16_Planar_Kinematics_of_a.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_16_Planar_Kinematics_of_a.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_16_Planar_Kinematics_of_a_Rigid_Body.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_16_Planar_Kinematics_of_a_Rigid_Body.ipynb
index 677b13e4..30a2bf09 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_16_Planar_Kinematics_of_a_Rigid_Body.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_16_Planar_Kinematics_of_a_Rigid_Body.ipynb
@@ -33,6 +33,7 @@
    "source": [
     "# Ex 16.2\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "alphaA = 2  #[radians per second square]\n",
@@ -123,6 +124,7 @@
    "source": [
     "# Ex 16.6\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "vA = 2  #[meters per second]\n",
@@ -170,6 +172,7 @@
    "source": [
     "# Ex 16.7\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Solution 1 Vector Analysis\n",
@@ -220,6 +223,7 @@
    ],
    "source": [
     "# Ex 16.8\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Link CB\n",
@@ -258,6 +262,7 @@
    ],
    "source": [
     "# Ex 16.9\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Link BC\n",
@@ -297,6 +302,7 @@
    "source": [
     "# Ex 16.10\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "vD = 3  #[meters per second]\n",
@@ -339,6 +345,7 @@
    ],
    "source": [
     "# Ex 16.12\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "x = 0.1/0.65   #[meters]\n",
@@ -376,6 +383,7 @@
     "# Ex 16.13\n",
     "import numpy as np\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "a = np.array([[math.cos(math.pi*45/180),0],[math.sin(math.pi*45/180),-10]])\n",
@@ -457,6 +465,7 @@
    "source": [
     "# Ex 16.16\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "w = 3  #[radians per second]\n",
@@ -539,6 +548,7 @@
     "# Ex 16.18\n",
     "import numpy as np\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "rB_x = -0.25*math.sin(math.pi*45/180)  #[meters]\n",
@@ -628,6 +638,7 @@
    ],
    "source": [
     "# Ex 16.20\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "vCDxyz = 1.2  #[meters per second]\n",
@@ -696,21 +707,21 @@
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_17_Planar_Kinetics_of_a_Rigid_Body_Force.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_17_Planar_Kinetics_of_a_Rigid_Body_Force.ipynb
index ea63db73..ea63db73 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_17_Planar_Kinetics_of_a_Rigid_Body_Force.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_17_Planar_Kinetics_of_a_Rigid_Body_Force.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_17_Planar_Kinetics_of_a_Rigid_Body_Force_and_Acceleration.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_17_Planar_Kinetics_of_a_Rigid_Body_Force_and_Acceleration.ipynb
index ea63db73..9bd668e0 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_17_Planar_Kinetics_of_a_Rigid_Body_Force_and_Acceleration.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_17_Planar_Kinetics_of_a_Rigid_Body_Force_and_Acceleration.ipynb
@@ -33,6 +33,7 @@
     "# Ex 17.2\n",
     "from scipy import integrate\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "y = lambda y: ((math.pi*2)/2)*y**(8)\n",
@@ -161,6 +162,7 @@
    "source": [
     "# Ex 17.5\n",
     "import numpy as np\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Using +ΣF_x = m(aG)_x, +ΣF_y = m(aG)_y and +ΣMG(counter clockwise)=0 \n",
@@ -202,6 +204,7 @@
    "source": [
     "# Ex 17.6\n",
     "import numpy as np\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "mm = 125  #[kilogram]\n",
@@ -248,6 +251,7 @@
    ],
    "source": [
     "# Ex 17.7\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "P = 600  #[Newton]\n",
@@ -299,6 +303,7 @@
     "# Ex 17.8\n",
     "import numpy as np\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "theta = 30  #[Degrees]\n",
@@ -344,6 +349,8 @@
    ],
    "source": [
     "# Ex 17.9\n",
+    "from __future__ import division\n",
+    "import math\n",
     "\n",
     "# Calculation\n",
     "# Using +ΣFx(right) = m(aG)x\n",
@@ -462,6 +469,7 @@
    "source": [
     "# Ex 17.11\n",
     "import numpy as np\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "m = 60  #[kilogram]\n",
@@ -564,6 +572,7 @@
    "source": [
     "# Ex 17.14\n",
     "import numpy as np\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation Solution 1\n",
     "IG = 8*0.35**(2)  #[kilogram meter square]\n",
@@ -722,21 +731,21 @@
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_18_Planar_Kinetics_of_a_Rigid_Body_Work.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_18_Planar_Kinetics_of_a_Rigid_Body_Work.ipynb
index 321b8558..321b8558 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_18_Planar_Kinetics_of_a_Rigid_Body_Work.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_18_Planar_Kinetics_of_a_Rigid_Body_Work.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_18_Planar_Kinetics_of_a_Rigid_Body_Work_and_Energy.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_18_Planar_Kinetics_of_a_Rigid_Body_Work_and_Energy.ipynb
index 321b8558..ec66b381 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_18_Planar_Kinetics_of_a_Rigid_Body_Work_and_Energy.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_18_Planar_Kinetics_of_a_Rigid_Body_Work_and_Energy.ipynb
@@ -171,6 +171,7 @@
    "source": [
     "# Ex 18.4\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "w2 = math.sqrt((700*9.81*0.05359)/63.875)  #[radians per second]\n",
@@ -214,6 +215,7 @@
    "source": [
     "# Ex 18.5\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "M = 75  #[Newton meter]\n",
@@ -253,6 +255,7 @@
    "source": [
     "# Ex 18.6\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "P = 50  #[Newton]\n",
@@ -378,6 +381,7 @@
    "source": [
     "# Ex 18.9\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Potential energy\n",
@@ -407,21 +411,21 @@
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_19_Planar_Kinetics_of_a_Rigid_Body_Impulse.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_19_Planar_Kinetics_of_a_Rigid_Body_Impulse.ipynb
index d7c43858..d7c43858 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_19_Planar_Kinetics_of_a_Rigid_Body_Impulse.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_19_Planar_Kinetics_of_a_Rigid_Body_Impulse.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_19_Planar_Kinetics_of_a_Rigid_Body_Impulse_and_Momentum.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_19_Planar_Kinetics_of_a_Rigid_Body_Impulse_and_Momentum.ipynb
index d7c43858..9bafb787 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_19_Planar_Kinetics_of_a_Rigid_Body_Impulse_and_Momentum.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_19_Planar_Kinetics_of_a_Rigid_Body_Impulse_and_Momentum.ipynb
@@ -131,7 +131,7 @@
    "source": [
     "# Ex 19.3\n",
     "import numpy as np\n",
-    "from __future__ import division \n",
+    "\n",
     "\n",
     "# Calculation\n",
     "IG = round(100*0.35**(2),3)  #[kilogram meter square]\n",
@@ -327,21 +327,21 @@
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_1_General_Principles.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_1_General_Principles.ipynb
index 62d27f1f..ec793839 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_1_General_Principles.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_1_General_Principles.ipynb
@@ -95,21 +95,21 @@
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "Python 2",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_2.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_2.ipynb
index 8b8efd6a..8b8efd6a 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_2.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_2.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_2_Force_Vectors.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_2_Force_Vectors.ipynb
index 8b8efd6a..51411f98 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_2_Force_Vectors.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_2_Force_Vectors.ipynb
@@ -34,6 +34,7 @@
    "source": [
     "#Example 2.1\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# The parallelogram law of addition is shown in Fig.2-10b\n",
     "\n",
@@ -86,6 +87,7 @@
    "source": [
     "# Example 2.2\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "F = 2000  #[newton]\n",
@@ -181,6 +183,7 @@
    "source": [
     "# Example 2.4\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Part(a) Refer fig 2-13b\n",
     "# Using parallelogram law\n",
@@ -234,6 +237,8 @@
    "source": [
     "# Example 2.5\n",
     "import math\n",
+    "from __future__ import division\n",
+    "\n",
     "# F1_x acts in -x direction and F1_y acts in +y direction Refer fig 2-17b\n",
     "\n",
     "# Calculation\n",
@@ -283,6 +288,7 @@
    "source": [
     "# Example 2.6\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "F1 = 600  #[Newton]\n",
@@ -389,6 +395,7 @@
    "source": [
     "# Example 2.8\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable declaration\n",
     "beta = 60  #[Degrees]\n",
@@ -506,6 +513,7 @@
    "source": [
     "# Example 2.10\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# For F1\n",
     "\n",
@@ -586,6 +594,7 @@
    "source": [
     "# Example 2.11\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable declaration\n",
     "\n",
@@ -910,6 +919,7 @@
    "source": [
     "# Example 2.16\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "rB_x = 2  #[meters]\n",
@@ -1036,21 +1046,21 @@
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_3_Equilibrium_of.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_3_Equilibrium_of.ipynb
index aef96ff3..aef96ff3 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_3_Equilibrium_of.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_3_Equilibrium_of.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_3_Equilibrium_of_a_Particle.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_3_Equilibrium_of_a_Particle.ipynb
index aef96ff3..7ae5e1a0 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_3_Equilibrium_of_a_Particle.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_3_Equilibrium_of_a_Particle.ipynb
@@ -34,6 +34,7 @@
     "# Example 3.2\n",
     "import math\n",
     "import numpy as np\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "theta = 30  #[Degrees]\n",
@@ -446,21 +447,21 @@
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_4_Force.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_4_Force.ipynb
index 7de45a57..7de45a57 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_4_Force.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_4_Force.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_4_Force_System_Resultants.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_4_Force_System_Resultants.ipynb
index 7de45a57..ddfa4a0f 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_4_Force_System_Resultants.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_4_Force_System_Resultants.ipynb
@@ -36,6 +36,7 @@
    "source": [
     "# Ex 4.1\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation Fig 4-4a\n",
     "MO = 100*2  #[Newton meter]\n",
@@ -137,6 +138,7 @@
    "source": [
     "# Ex 4.3\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Assuming positive moments act in +k direction i.e counterclockwise\n",
@@ -173,6 +175,7 @@
     "# Ex 4.4\n",
     "import math\n",
     "import numpy as np\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "F = 60  #[Newton]\n",
@@ -384,6 +387,7 @@
     "# Example 4.7\n",
     "import math\n",
     "import numpy as np \n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "F = 400  #[Newton]\n",
@@ -666,6 +670,8 @@
    "source": [
     "# Example 4.12\n",
     "import math\n",
+    "from __future__ import division\n",
+    "import numpy as np\n",
     "\n",
     "# Variable Declaration\n",
     "rA_x = 0   #[meter]\n",
@@ -813,6 +819,7 @@
    "source": [
     "# Example 4.14\n",
     "import math \n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Let resultant force be FR\n",
@@ -927,6 +934,7 @@
     "# Example 4.16\n",
     "import math\n",
     "from __future__ import division\n",
+    "\n",
     "# Calculation\n",
     "FR_x = 500*math.cos(math.pi*60/180)+100  #[Newton]\n",
     "FR_y = -500*math.sin(math.pi*60/180)+200  #[Newton]\n",
@@ -1018,6 +1026,7 @@
    ],
    "source": [
     "# Example 4.18\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# +FR = ΣF Refer Fig 4-45a\n",
@@ -1063,6 +1072,7 @@
     "# Example 4.19\n",
     "import math\n",
     "import numpy as np\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "FR_x = 0  #[Newton]\n",
@@ -1123,6 +1133,7 @@
     "# Example 4.20\n",
     "from scipy import integrate\n",
     "import numpy as np\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# The coloured differential area element dA = wdx = 60x**(2)\n",
@@ -1206,6 +1217,7 @@
    ],
    "source": [
     "# Example 4.22\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Refer Fig 4-50b\n",
@@ -1241,21 +1253,21 @@
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_5_Equilibrium_of_a.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_5_Equilibrium_of_a.ipynb
index b3b5669a..b3b5669a 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_5_Equilibrium_of_a.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_5_Equilibrium_of_a.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_5_Equilibrium_of_a_Rigid_Body.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_5_Equilibrium_of_a_Rigid_Body.ipynb
index b3b5669a..e9f9fc0d 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_5_Equilibrium_of_a_Rigid_Body.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_5_Equilibrium_of_a_Rigid_Body.ipynb
@@ -34,6 +34,7 @@
    "source": [
     "# Example 5.6\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Summing forces in the x direction +ΣF_x(right) = 0\n",
@@ -128,6 +129,7 @@
    "source": [
     "# Example 5.8\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Summing moments about A, we obtain direct solution for NB\n",
@@ -220,6 +222,7 @@
     "# Example 5.10\n",
     "import math\n",
     "import numpy as np\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Refer Fig 5-18b\n",
@@ -269,6 +272,7 @@
     "# Example 5.11\n",
     "import math\n",
     "import numpy as np\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Since ΣMO = 0 angle theta which defines the line of action of FA can be determined by trigonometry\n",
@@ -315,6 +319,7 @@
    ],
    "source": [
     "# Example 5.13\n",
+    "import numpy as np\n",
     "\n",
     "# Calculation\n",
     "# Using ΣF_x = 0ΣF_z = 0\n",
@@ -367,6 +372,7 @@
    "source": [
     "# Example 5.14\n",
     "import math \n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Using right hand rule and assuming positive moments act in +i direction, ΣM_x = 0\n",
@@ -518,6 +524,7 @@
    ],
    "source": [
     "# Example 5.17\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Using u.(rB X TB + rE X W)\n",
@@ -539,21 +546,21 @@
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_6.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_6.ipynb
index 4fe7e652..4fe7e652 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_6.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_6.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_6_Structural_Analysis.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_6_Structural_Analysis.ipynb
index 4fe7e652..80b876b6 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_6_Structural_Analysis.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_6_Structural_Analysis.ipynb
@@ -37,6 +37,7 @@
    "source": [
     "# Example 6.1\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "\n",
@@ -98,6 +99,7 @@
     "# Example 6.2\n",
     "import math\n",
     "import numpy as np\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Joint C\n",
@@ -340,6 +342,7 @@
    "source": [
     "# Example 6.7\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Using  +ΣMB(counterclockwise) = 0\n",
@@ -389,6 +392,7 @@
     "# Example 6.8\n",
     "import numpy as np\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# At joint A, ΣF_x = 0, ΣF_y = 0, ΣF_z = 0\n",
@@ -554,6 +558,7 @@
    "source": [
     "# Example 6.16\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Using  +ΣMA(counterclockwise) = 0\n",
@@ -605,6 +610,7 @@
    ],
    "source": [
     "# Example 6.17\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Consider entire frame\n",
@@ -661,6 +667,7 @@
    ],
    "source": [
     "# Example 6.18\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Using equations of equilibrium\n",
@@ -746,21 +753,21 @@
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_7.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_7.ipynb
index 013e54d4..013e54d4 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_7.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_7.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_7_Internal_Forces.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_7_Internal_Forces.ipynb
index 013e54d4..b26a181a 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_7_Internal_Forces.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_7_Internal_Forces.ipynb
@@ -228,6 +228,7 @@
    "source": [
     "# Example 7.5\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Using  +ΣF_y(upward) = 0 Refer fig 7-8b\n",
@@ -369,21 +370,21 @@
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_8.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_8.ipynb
index f2059979..f2059979 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_8.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_8.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_8_Friction.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_8_Friction.ipynb
index f2059979..6f84215f 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_8_Friction.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_8_Friction.ipynb
@@ -34,6 +34,7 @@
    "source": [
     "# Example 8.1\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "P = 80  #[Newton]\n",
@@ -79,6 +80,7 @@
    "source": [
     "# Ex 8.2\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# W*sin25 = us(W*cos25)\n",
@@ -149,6 +151,7 @@
    "source": [
     "# Ex 8.4\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "# Using +ΣF_x(right) = 0,FA = F and NA = N for bottom pipe\n",
@@ -191,6 +194,7 @@
    "source": [
     "# Ex 8.5\n",
     "import numpy as np\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "uB = 0.2\n",
@@ -254,6 +258,7 @@
     "# Ex 8.6\n",
     "import math\n",
     "import numpy as np\n",
+    "from __future__ import division\n",
     "\n",
     "# Variable Declaration\n",
     "usA = 0.15\n",
@@ -384,21 +389,21 @@
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_9_Center_of_Gravity.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_9_Center_of_Gravity.ipynb
index 92c855af..92c855af 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_9_Center_of_Gravity.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_9_Center_of_Gravity.ipynb
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_9_Center_of_Gravity_and_Centroid.ipynb b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_9_Center_of_Gravity_and_Centroid.ipynb
index 92c855af..6b43eee2 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/Chapter_9_Center_of_Gravity_and_Centroid.ipynb
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/Chapter_9_Center_of_Gravity_and_Centroid.ipynb
@@ -34,6 +34,7 @@
     "# Example 9.1\n",
     "from scipy import integrate\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "a = lambda y: y**(2)*math.sqrt(4*y**(2)+1)\n",
@@ -192,6 +193,7 @@
     "# Example 9.7\n",
     "from scipy import integrate\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "a = lambda y: 100*math.pi*y**(2)\n",
@@ -230,6 +232,7 @@
     "# Example 9.8\n",
     "from scipy import integrate\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "a = lambda z: z*200*z*math.pi*0.5**(2)\n",
@@ -267,6 +270,7 @@
    "source": [
     "# Example 9.9\n",
     "import math\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "xbar = (60*math.pi*60+0*40+0*20)/(math.pi*60+40+20)  #[millimeter]\n",
@@ -304,6 +308,7 @@
    ],
    "source": [
     "# Example 9.10\n",
+    "from __future__ import division\n",
     "\n",
     "# Calculation\n",
     "xbar = (1*0.5*3*3+(-1.5)*3*3+(-2.5)*(-2)*1)/(0.5*3*3+3*3+(-2)*1)  #[meter]\n",
@@ -442,6 +447,7 @@
    "source": [
     "# Example 9.14\n",
     "from __future__ import division\n",
+    "import math\n",
     "\n",
     "# Variable Declaration\n",
     "b = 5  #[meter]\n",
@@ -515,21 +521,21 @@
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python [default]",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.12"
+   "pygments_lexer": "ipython3",
+   "version": "3.6.0"
   }
  },
  "nbformat": 4,
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/screenshots/plot1.png b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/screenshots/plot1.png
index deb1e879..deb1e879 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/screenshots/plot1.png
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/screenshots/plot1.png
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/screenshots/plot2.png b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/screenshots/plot2.png
index b75faff2..b75faff2 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/screenshots/plot2.png
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/screenshots/plot2.png
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/screenshots/plot3.png b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/screenshots/plot3.png
index c3b384fc..c3b384fc 100644
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/screenshots/plot3.png
+++ b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibbeler_and_Gupta/screenshots/plot3.png
diff --git a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/index.png b/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/index.png
deleted file mode 100644
index 491fb7a8..00000000
--- a/Engineering_Mechanics_Statics_and_Dynamics_by_Hibler_and_Gupta/index.png
+++ /dev/null