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diff --git a/Engineering_Physics_By_G_Vijayakumari/Chapter7.ipynb b/Engineering_Physics_By_G_Vijayakumari/Chapter7.ipynb new file mode 100755 index 00000000..13a2a17f --- /dev/null +++ b/Engineering_Physics_By_G_Vijayakumari/Chapter7.ipynb @@ -0,0 +1,781 @@ +{
+ "cells": [
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "#7: Conducting Materials"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "##Example number 7.1, Page number 178"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 4,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "The current density in the conductor corresponds to a drift velocity is 5.9 *10**9 A m^-1\n",
+ "Mobility of the charge carrires is 6.58898 *10**-3 m^2 V^-1 s^-1\n"
+ ]
+ }
+ ],
+ "source": [
+ "#importing modules\n",
+ "import math\n",
+ "from __future__ import division\n",
+ "\n",
+ "#Variable declaration\n",
+ "n=5.9*10**28; #electron concentration of conductor(m^-3)\n",
+ "v=0.625; #drift velocity of a conductor(ms^-1)\n",
+ "x=6.22*10**7; #electrical conductivity(ohm^-1 m^-1)\n",
+ "e=1.6*10**-19; #charge of electron(c)\n",
+ "\n",
+ "#Calculation\n",
+ "J=n*e*v; #current density in the conductor corresponds to drift velocity(Am^-1)\n",
+ "z=x/(n*e); #mobility of the charge(m^2V^-1s^-1)\n",
+ " \n",
+ "#Result\n",
+ "print \"The current density in the conductor corresponds to a drift velocity is\",J/10**9,\"*10**9 A m^-1\"\n",
+ "print \"Mobility of the charge carrires is\",round(z*10**3,5),\"*10**-3 m^2 V^-1 s^-1\"\n"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "##Example number 7.2, Page number 179"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 6,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "The drift velocity of free electron in a copper wire is 7.0028 *10**-5 ms^-1\n"
+ ]
+ }
+ ],
+ "source": [
+ "#importing modules\n",
+ "import math\n",
+ "from __future__ import division\n",
+ "\n",
+ "#Variable declaration\n",
+ "n=8.5*10**28; #density of free electrons in copper(m^-3)\n",
+ "A=1.05*10**-6; #sectional area of copper(m^2)\n",
+ "e=1.6*10**-19; #charge of electron(c)\n",
+ "I=1; #copper wire carries a current(A)\n",
+ "\n",
+ "#Calculation\n",
+ "V=1/(A*n*e); #drift velocity of free electrons in copper wire(ms^-1)\n",
+ "\n",
+ "#Result\n",
+ "print \"The drift velocity of free electron in a copper wire is\",round(V*10**5,4),\"*10**-5 ms^-1\""
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "##Example number 7.3, Page number 179"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 3,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "The drift velocity of free electrons in copper is 1.75 *10**-3 ms^-1\n"
+ ]
+ }
+ ],
+ "source": [
+ "#importing modules\n",
+ "import math\n",
+ "from __future__ import division\n",
+ "\n",
+ "#Variable declaration\n",
+ "X=3.5*10**-3; #mobility of free electrons in copper(m^2 V^-1 s^-1)\n",
+ "E=0.5; #elactric field strength of copper(V m^-1)\n",
+ "\n",
+ "#Calculation\n",
+ "V=X*E; #drift velocity of free electrons in copper(m s^-1)\n",
+ "\n",
+ "#Result\n",
+ "print \"The drift velocity of free electrons in copper is\",V*10**3,\"*10**-3 ms^-1\""
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "##Example number 7.4, Page number 179"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 5,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "The relaxation time of conduction electrons is 3.815 *10**-14 s\n"
+ ]
+ }
+ ],
+ "source": [
+ "#importing modules\n",
+ "import math\n",
+ "from __future__ import division\n",
+ "\n",
+ "#Variable declaration\n",
+ "n=6.5*10**28; #conduction electron(m^-3)\n",
+ "r=1.435*10**-8; #metal resistivity(ohm-metre)\n",
+ "e=1.6*10**-19; #charge of electron(c)\n",
+ "m=9.11*10**-31; #mass of a electron(kg)\n",
+ "\n",
+ "#Calculation\n",
+ "T=m/(r*n*e**2); #relaxation time of conduction electrons(s)\n",
+ "\n",
+ "#Result\n",
+ "print \"The relaxation time of conduction electrons is\",round(T*10**14,3),\"*10**-14 s\""
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "##Example number 7.5, Page number 180"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 9,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "The mean free path between collision of free electrons in copper is 2.8153 *10**-9 m\n",
+ "answer varies due to rounding off errors\n"
+ ]
+ }
+ ],
+ "source": [
+ "#importing modules\n",
+ "import math\n",
+ "from __future__ import division\n",
+ "\n",
+ "#Variable declaration\n",
+ "r=1.72*10**-8; #resistivity of copper(ohm metre)\n",
+ "T=293; #temperature of copper(K)\n",
+ "n=8.48*10**28; #density of free electron(m^-3)\n",
+ "e=1.6*10**-19; #charge of electron(c)\n",
+ "m=9.11*10**-31; #mass of a electron(kg)\n",
+ "k=1.38*10**-23; #boltzmann constant(m^2 Kg s^-2 k^-1)\n",
+ "\n",
+ "#Calculation\n",
+ "t=m/(r*n*(e**2)); #relaxation time(s)\n",
+ "v=math.sqrt(3*k*T/m); #thermal velocity(ms^-1)\n",
+ "Lamda=t*v; #mean free path between collision of free electrons in copper(m)\n",
+ "\n",
+ "#Result\n",
+ "print \"The mean free path between collision of free electrons in copper is\",round(Lamda*10**9,4),\"*10**-9 m\"\n",
+ "print \"answer varies due to rounding off errors\""
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "##Example number 7.6, Page number 180"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 12,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "The thermal velocity is 116.76 *10**3 m s^-1\n",
+ "Drift velocity of electrons is 40.0 m s^-1\n",
+ "Thus the terminal velocity is high compared to the drift velocity\n"
+ ]
+ }
+ ],
+ "source": [
+ "#importing modules\n",
+ "import math\n",
+ "from __future__ import division\n",
+ "\n",
+ "#Variable declaration\n",
+ "t=1*10**-3; #thickness of metal(m)\n",
+ "V=1; #potential difference applied in volts(V)\n",
+ "T=300; #temperature(K)\n",
+ "m=0.04; #mobility(m^2 V^-1 s^-1)\n",
+ "k=1.38*10**-23; #boltzmann constant(m^2 Kg s^-2 k^-1)\n",
+ "m1=9.11*10**-31; #mass of a electron(kg)\n",
+ "\n",
+ "#Calculation\n",
+ "v=math.sqrt(3*k*T/m1); #thermal velocity(ms^-1)\n",
+ "E=V/t; #unit potenyial voltage gradient(V m^-1)\n",
+ "vd=E*m; #drift velocity of electrons(m s^-1)\n",
+ "\n",
+ "#Result\n",
+ "print \"The thermal velocity is\",round(v/10**3,2),\"*10**3 m s^-1\"\n",
+ "print \"Drift velocity of electrons is\",vd,\"m s^-1\"\n",
+ "print \"Thus the terminal velocity is high compared to the drift velocity\""
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "##Example number 7.7, Page number 181"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 15,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "The electrical conductivity of copper is 5.9 *10**7 S m^-1\n",
+ "answer varies due to rounding off errors\n"
+ ]
+ }
+ ],
+ "source": [
+ "#importing modules\n",
+ "import math\n",
+ "from __future__ import division\n",
+ "\n",
+ "#Variable declaration\n",
+ "AW=63.5; #atomic weight of copper\n",
+ "D=8.93*10**3; #density of copper(kg m^-3)\n",
+ "t=2.48*10**-14; #relaxation time of copper(s)\n",
+ "AV=6.023*10**26; #avagadro no(mole^-1)\n",
+ "e=1.6*10**-19; #charge of electron(c)\n",
+ "m=9.11*10**-31; #mass of a electron(kg)\n",
+ "\n",
+ "#Calculation\n",
+ "n=AV*D/AW; #density of electrons per unit volume(m^-3)\n",
+ "sigma=n*e**2*t/m; #electrical conductivity of copper(Sm^-1)\n",
+ "\n",
+ "#Result\n",
+ "print \"The electrical conductivity of copper is\",round(sigma/10**7,1),\"*10**7 S m^-1\"\n",
+ "print \"answer varies due to rounding off errors\""
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "##Example number 7.8, Page number 181"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 19,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "The drift velocity in copper is 3.6657 *10**-6 ms^-1\n",
+ "The current density in copper is 4.9736 *10**4 Am^-2\n",
+ "answer varies due to rounding off errors\n"
+ ]
+ }
+ ],
+ "source": [
+ "#importing modules\n",
+ "import math\n",
+ "from __future__ import division\n",
+ "\n",
+ "#Variable declaration\n",
+ "I=10; #current(A)\n",
+ "r=0.8*10**-2; #radius of wire(m)\n",
+ "n=8.48*10**28; #density of free electron(m^-3)\n",
+ "e=1.6*10**-19; #charge of electron(c)\n",
+ "\n",
+ "#Calculation\n",
+ "J=I/(math.pi*r**2); #current density of copper(Am^-2)\n",
+ "v=J/(n*e); #drift velocity of copper(ms^-1)\n",
+ "\n",
+ "#Result\n",
+ "print \"The drift velocity in copper is\",round(v*10**6,4),\"*10**-6 ms^-1\"\n",
+ "print \"The current density in copper is\",round(J/10**4,4),\"*10**4 Am^-2\"\n",
+ "print \"answer varies due to rounding off errors\""
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "##Example number 7.9, Page number 182"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 22,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "The mobility of charge is 6.997 *10**-3 m^2 V^-1 s^-1\n",
+ "The drift velocity of electrons is 0.6997 m s^-1\n"
+ ]
+ }
+ ],
+ "source": [
+ "#importing modules\n",
+ "import math\n",
+ "from __future__ import division\n",
+ "\n",
+ "#Variable declaration\n",
+ "r=1.54*10**-8; #resistivity of silver wire at room temperature(ohm metre)\n",
+ "E=100; #Electric field along the wire(V/m)\n",
+ "n=5.8*10**28; #n is assuming of conduction electrons(m^-3)\n",
+ "e=1.6*10**-19; #charge of electron(c)\n",
+ "\n",
+ "#Calculation\n",
+ "mew=1/(r*n*e); #mobility of charge(m^2 V^-1 s^-1)\n",
+ "vd=mew*E; #drift velocity of electrons(m s^-1)\n",
+ "\n",
+ "#Result\n",
+ "print \"The mobility of charge is\",round(mew*10**3,3),\"*10**-3 m^2 V^-1 s^-1\"\n",
+ "print \"The drift velocity of electrons is\",round(vd,4),\"m s^-1\""
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "##Example number 7.10, Page number 182"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 5,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "The relaxation time collision of electrons in copper obeying classical laws is 2.43 *10**-14 s\n",
+ "The mobility charge of copper obeying classical laws is 0.427 *10**-2 m^2 V^-1 s^-1\n"
+ ]
+ }
+ ],
+ "source": [
+ "#importing modules\n",
+ "import math\n",
+ "from __future__ import division\n",
+ "\n",
+ "#Variable declaration\n",
+ "D=8.92*10**3; #density of copper(kg m^-3)\n",
+ "AW=63.5; #atomic weight of copper\n",
+ "r=1.73*10**-8; #resistivity of copper(ohm metre)\n",
+ "AV=6.023*10**26; #avagadro no(mole^-1)\n",
+ "e=1.6*10**-19; #charge of electron(c)\n",
+ "m=9.11*10**-31; #mass of a electron(kg)\n",
+ "\n",
+ "#Calculation\n",
+ "n=AV*D/AW; #density of electrons per unit volume(m^-3)\n",
+ "tow=m/(r*n*e**2); #average time collision of electrons in copper(s)\n",
+ "mew=1/(r*n*e); #mobility of charge(m^2 V^-1 s^-1)\n",
+ "\n",
+ "#Result\n",
+ "print \"The relaxation time collision of electrons in copper obeying classical laws is\",round(tow*10**14,2),\"*10**-14 s\"\n",
+ "print \"The mobility charge of copper obeying classical laws is\",round(mew*10**2,3),\"*10**-2 m^2 V^-1 s^-1\""
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "##Example number 7.11, Page number 183"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 6,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "The electrical resistivity is 4.63 *10**-8 ohm metre\n",
+ "answer varies due to rounding off errors\n"
+ ]
+ }
+ ],
+ "source": [
+ "#importing modules\n",
+ "import math\n",
+ "from __future__ import division\n",
+ "\n",
+ "#Variable declaration\n",
+ "r=1.85*10**-10; #the radius of sodium atom(m)\n",
+ "t=3*10**-14; #the classic value of mean free time(sec)\n",
+ "temp=0; #temperature(centigrade)\n",
+ "na=2; #number of atoms in a unit cell\n",
+ "ne=1; #number of electrons per unit cell\n",
+ "e=1.6*10**-19; #charge of electron(c)\n",
+ "m=9.11*10**-31; #mass of a electron(kg)\n",
+ "\n",
+ "#Calculation \n",
+ "a=4*r/math.sqrt(3); #a is one side in bcc structure unit cell(m)\n",
+ "v=a**3; #volume of bcc structure unit cell(m^3)\n",
+ "n=na*ne/v; #density of electrons per unit volume(m^-3)\n",
+ "rho=m/(n*e**2*t); #The electrical resistivity(ohm metre)\n",
+ "\n",
+ "#Result\n",
+ "print \"The electrical resistivity is\",round(rho*10**8,2),\"*10**-8 ohm metre\"\n",
+ "print \"answer varies due to rounding off errors\""
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "##Example number 7.12, Page number 184"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 15,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "Free electron concentration in aluminium is 0.18 V/m\n",
+ "Mobility of the charge is 1.28 *10**-3 m^2 V^-1 S^-1\n",
+ "The drift velocity of electrons is 2.304 *10**-4 m s^-1\n",
+ "answer varies due to rounding off errors\n"
+ ]
+ }
+ ],
+ "source": [
+ "#importing modules\n",
+ "import math\n",
+ "from __future__ import division\n",
+ "\n",
+ "#Variable declaration\n",
+ "rho=2.7*10**-8; #electrical resistivity of aluminium(ohm metre)\n",
+ "AW=26.98; #atomic weight of aluminium\n",
+ "d=2.7*10**3; #density of volume(Kg/m^3)\n",
+ "R=60*10**-3; #resistance(W)\n",
+ "l=5; #length of aluminium wire(m)\n",
+ "i=15; #aluminuim wire carries a current(A)\n",
+ "fe=3; #number of free electrons \n",
+ "AV=6.023*10**26; #avagadro no(mole^-1)\n",
+ "e=1.6*10**-19; #charge of electron(c)\n",
+ "\n",
+ "#Calculation\n",
+ "n=AV*d*fe/AW; #density of electrons per unit volume(electrons/m^-3)\n",
+ "mew=1/(n*e*rho); #mobility of the charge(m^2 V^-1 S^-1)\n",
+ "E=i*R/l; #free electron concentration(V/m)\n",
+ "vd=mew*E; #drift velocity(m s^-1)\n",
+ "\n",
+ "#Result\n",
+ "print \"Free electron concentration in aluminium is\",E,\"V/m\"\n",
+ "print \"Mobility of the charge is\",round(mew*10**3,2),\"*10**-3 m^2 V^-1 S^-1\"\n",
+ "print \"The drift velocity of electrons is\",round(vd*10**4,3),\"*10**-4 m s^-1\"\n",
+ "print \"answer varies due to rounding off errors\""
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "##Example number 7.13, Page number 184"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 21,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "The resistance of an intrinsic Ge rod is 4310 ohm\n"
+ ]
+ }
+ ],
+ "source": [
+ "#importing modules\n",
+ "import math\n",
+ "from __future__ import division\n",
+ "\n",
+ "#Variable declaration\n",
+ "l=1*10**-2; #length of intrinsic Ge rod(m)\n",
+ "b=1*10**-3; #breadth of intrinsic Ge rod(m)\n",
+ "t=1*10**-3; #thickness of intrinsic Ge rod(m)\n",
+ "temp=300; #temperature(K)\n",
+ "d=2.5*10**19; #intrinsic carrier density(Kg/m^3)\n",
+ "z=0.39; #mobility of electron(m^2 V^-1 S^-1)\n",
+ "zh=0.19; #mobility of hole(m^2 V^-1 S^-1) \n",
+ "e=1.6*10**-19; #charge of electron(c)\n",
+ "\n",
+ "#Calculation\n",
+ "x=d*e*(z+zh); #electrical conductivity(ohm^-1 m^-1)\n",
+ "r=1/x; #electrical resistivity(ohm metre)\n",
+ "A=b*t; #area(m^2)\n",
+ "R=r*l/A; #resistance of an intrinsic Ge rod(ohm)\n",
+ "\n",
+ "#Result\n",
+ "print \"The resistance of an intrinsic Ge rod is\",int(R),\"ohm\""
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "##Example number 7.14, Page number 188"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 19,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "The thermal conductivity of copper is 189.9299 W m^-1 K^-1\n"
+ ]
+ }
+ ],
+ "source": [
+ "#importing modules\n",
+ "import math\n",
+ "from __future__ import division\n",
+ "\n",
+ "#Variable declaration\n",
+ "d=8.48*10**28; #free electron density of copper(m^-3)\n",
+ "y=2.8138*10**-9; #mean free path(m)\n",
+ "v=1.1536*10**5; #velocity of copper(m s^-1)\n",
+ "t=20; #temperature of copper(C)\n",
+ "Kb=1.38*10**-23; #Boltzmann's constant(m^2 Kg s^-2 k^-1)\n",
+ "\n",
+ "#Calculation\n",
+ "K=1/2*(d*v*y*Kb); #thermal conductivity of copper(W m^-1 K^-1)\n",
+ "\n",
+ "#Result\n",
+ "print \"The thermal conductivity of copper is\",round(K,4),\"W m^-1 K^-1\""
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "##Example number 7.15, Page number 189"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 22,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "The thermal conductivity of brass is 14.64 W m^-1 K^-1\n",
+ "The thermal resistance of brass is 4.503 K W^-1\n",
+ "answer varies due to rounding off errors\n"
+ ]
+ }
+ ],
+ "source": [
+ "#importing modules\n",
+ "import math\n",
+ "from __future__ import division\n",
+ "\n",
+ "#Variable declaration\n",
+ "er=50*10**-8; #electrical resistivity(ohm metre)\n",
+ "t=300; #temperature(K)\n",
+ "r=13*10**-3; #radius of brass(m)\n",
+ "th=35*10**-3; #thickness of brass(m)\n",
+ "L=2.44*10**-8; #Lorentz number(W ohm K^-2)\n",
+ "\n",
+ "#Calculation\n",
+ "K=L*t/er; #thermal conductivity of brass(W m^-1 K^-1)\n",
+ "A=math.pi*r**2; #area of brass disk(m^2)\n",
+ "Rt=th/(K*A); #thermal resistance of brass(K W^-1)\n",
+ "\n",
+ "#Result\n",
+ "print \"The thermal conductivity of brass is\",K,\"W m^-1 K^-1\"\n",
+ "print \"The thermal resistance of brass is\",round(Rt,3),\"K W^-1\"\n",
+ "print \"answer varies due to rounding off errors\""
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "##Example number 7.16, Page number 189"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 24,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "Lorentz number is 2.2094 *10**-8 W ohm K^-2\n"
+ ]
+ }
+ ],
+ "source": [
+ "#importing modules\n",
+ "import math\n",
+ "from __future__ import division\n",
+ "\n",
+ "#Variable declaration\n",
+ "x=5.87*10**7; #electrical conductivity(ohm^-1 m^-1)\n",
+ "k=380; #thermal conductivity of copper(W m-1 K^-1)\n",
+ "t=293; #temperature of copper(K)\n",
+ "\n",
+ "#Calculation\n",
+ "L=k/(x*t); #Lorentz number(W ohm K^-2)\n",
+ "\n",
+ "#Result\n",
+ "print \"Lorentz number is\",round(L*10**8,4),\"*10**-8 W ohm K^-2\""
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "##Example number 7.17, Page number 189"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 25,
+ "metadata": {
+ "collapsed": false
+ },
+ "outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "The thermal conductivity of copper is 468.48 W m^-1 K^-1\n"
+ ]
+ }
+ ],
+ "source": [
+ "#importing modules\n",
+ "import math\n",
+ "from __future__ import division\n",
+ "\n",
+ "#Variable declaration\n",
+ "x=6.40*10**7; #electrical conductivity(mho m^-1)\n",
+ "t=300; #temperature of copper(K)\n",
+ "L=2.44*10**-8; #Lorentz number(W ohm K^-2)\n",
+ "\n",
+ "#Calculation\n",
+ "K=x*t*L; #thermal conductivity of copper(W m^-1 K^-1)\n",
+ "\n",
+ "#Result\n",
+ "print \"The thermal conductivity of copper is\",K,\"W m^-1 K^-1\""
+ ]
+ }
+ ],
+ "metadata": {
+ "kernelspec": {
+ "display_name": "Python 2",
+ "language": "python",
+ "name": "python2"
+ },
+ "language_info": {
+ "codemirror_mode": {
+ "name": "ipython",
+ "version": 2
+ },
+ "file_extension": ".py",
+ "mimetype": "text/x-python",
+ "name": "python",
+ "nbconvert_exporter": "python",
+ "pygments_lexer": "ipython2",
+ "version": "2.7.9"
+ }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
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