{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "\n", "# chapter1: De Broglie Matter Waves" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##example 1.1;page no:10" ] }, { "cell_type": "code", "execution_count": 3, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.1,page no:10\n", "\n", " de Broglie wavelength of earth in metres is= 3.68e-63\n" ] } ], "source": [ "# cal of de brogle wavelength of earth\n", "#intiation of all variables \n", "#given that\n", "M = 6.*10**24 # Mass of earth in Kg\n", "v = 3.*10**4 # Orbital velocity of earth in m/s\n", "h = 6.625*10**-34 # Plank constant\n", "print(\"Example 1.1,page no:10\")\n", "lamda=h/(M*v) \n", "print(\"\\n de Broglie wavelength of earth in metres is=\"),round(lamda,65)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.2;page no:10" ] }, { "cell_type": "code", "execution_count": 4, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.2,page no:11\n", "\n", " de Broglie wavelength of body in metres is= 6.625e-35\n" ] } ], "source": [ "#cal of de Broglie wavelength of body\n", "#intiation of all variables\n", "#given that\n", "M = 1 # Mass of object in Kg\n", "v = 10 # velocity of object in m/s\n", "h = 6.625*10**-34 # Plank constant\n", "print(\"Example 1.2,page no:11\");\n", "lamda=h/(M*v)#calculation of de Broglie wavelength\n", "print(\"\\n de Broglie wavelength of body in metres is=\"),round(lamda,38)\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##example 1.3;page no:11" ] }, { "cell_type": "code", "execution_count": 5, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.3,page no:11\n", "\n", " de Broglie wavelength of body in metres is= 6.625e-09\n" ] } ], "source": [ "#cal of de brogle wavelength of body\n", "#intiation of all variables \n", "# Given that\n", "m = 1e-30 # Mass of any object in Kg\n", "v = 1e5 # velocity of object in m/s\n", "h = 6.625e-34 # Plank constant\n", "print(\"Example 1.3,page no:11\")\n", "lamda=h/(m*v) # calculation of de Broglie wavelength in metres\n", "print(\"\\n de Broglie wavelength of body in metres is=\"),round(lamda,12)\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##example 1.4;page no:15" ] }, { "cell_type": "code", "execution_count": 6, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.4,page no:15\n", "velocity of electron in m/s: 1000.0\n", "momentum of electron in Kgm/s: 9.1e-28\n", "de Broglie wavelength of electron is: 7.27e-07\n", "Note:The value given in the book for lamda is wrong hence corrected above\n" ] } ], "source": [ "#cal of velocity,momenteum and wave lenght of electron\n", "#intiation of all variables \n", "# Given that\n", "import math\n", "KE = 4.55e-25 # Kinetic energy of an electron in Joule\n", "m = 9.1e-31 # Mass of any object in Kg\n", "h = 6.62e-34 # Plank constant\n", "print(\"Example 1.4,page no:15\")\n", "v = math.sqrt(2*KE/m) # Calculation of velocity of moving electron\n", "p = m*v #Calculation of momentum of moving electron\n", "lamda= h/p # calculation of de Broglie wavelength\n", "print(\"velocity of electron in m/s:\"),round(v)\n", "print(\"momentum of electron in Kgm/s:\"),round(p,29)\n", "print(\"de Broglie wavelength of electron is:\"),round(lamda,9)\n", "print(\"Note:The value given in the book for lamda is wrong hence corrected above\")\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.5;page no:16" ] }, { "cell_type": "code", "execution_count": 7, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.5,page no:16\n", "de Broglie wavelength of proton is: 2.645e-14\n" ] } ], "source": [ "#cal of de brogle wavelength of proton\n", "#intiation of all variables \n", "#Given that\n", "c = 3e8 # speed of light in m/s\n", "v = c/20 # Speed of proton in m/s\n", "m = 1.67e-27 # Mass of proton in Kg\n", "h = 6.625e-34 # Plank constant\n", "print(\"Example 1.5,page no:16\")\n", "lamda= h/(m*v) # calculation of de Broglie wavelength\n", "print(\"de Broglie wavelength of proton is:\"),round(lamda,17)\n", "# Answer in book is 6.645e-14m which is a calculation mistake\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.6;page no:16" ] }, { "cell_type": "code", "execution_count": 1, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.6,page no:16\n", "\n", " de Broglie wavelength of neutron in angstrom= 7.99e-05\n" ] } ], "source": [ "#cal of de brogle wavelength of neutron\n", "#intiation of all variables \n", "#given that\n", "import math\n", "e = 12.8 # Energy of neutron in MeV\n", "c = 3.e8 # speed of light in m/s\n", "m = 1.675e-27 # Mass of neutron in Kg\n", "h = 6.62e-34 # Plank constant\n", "print(\"Example 1.6,page no:16\")\n", "rest_e = m*c**2/(1e6*1.6e-19)# rest mass energy of neutron in MeV\n", "if e/rest_e < 0.015:\n", "\tE = e\n", "else:\n", "\tE = rest_e +e\n", "lamda = h/(math.sqrt(2*m*e*1e6*1.6e-19)) # calculation of de Broglie wavelength\n", "print(\"\\n de Broglie wavelength of neutron in angstrom=\"),round(lamda*1e10,7)\n", "# Answer in book is 8.04e-5 angstrom which is misprinted\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.7;page no:17" ] }, { "cell_type": "code", "execution_count": 7, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.7,page no:17\n", "\n", " de Broglie wavelength of neutron in angstrom= 1.734\n" ] } ], "source": [ "#cal of de brogle wavelength of neutron\n", "#intiation of all variables \n", "#Given that\n", "import math\n", "e = 1.602e-19 # charge on electron in coulomb\n", "V = 50. # Applied voltage in volts\n", "m = 9.1e-31 # Mass of electron in Kg\n", "h = 6.62e-34 # Plank constant\n", "print(\"Example 1.7,page no:17\")\n", "lamda= h/(math.sqrt(2*e*V*m)) # calculation of de Broglie wavelength\n", "print(\"\\n de Broglie wavelength of neutron in angstrom=\"),round(lamda*1e10,3)\n", "\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.9;page no:18" ] }, { "cell_type": "code", "execution_count": 8, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.9,page no:18\n", "de Broglie wavelength associated with the electron in angstrom= 1.67\n" ] } ], "source": [ "#cal of de brogle wavelength associated with the electron\n", "#intiation of all variables \n", "#Given that\n", "import math\n", "e = 1.6e-19 # charge on electron in coulomb\n", "V = 54 # Applied voltage in volts\n", "m = 9.1e-31 # Mass of electron in Kg\n", "h = 6.63e-34 # Plank constant\n", "print(\"Example 1.9,page no:18\")\n", "lamda = h/(math.sqrt(2*e*V*m)) # calculation of de Broglie wavelength\n", "print(\"de Broglie wavelength associated with the electron in angstrom=\"),round(lamda*1e10,2)\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.10;page no:19" ] }, { "cell_type": "code", "execution_count": 9, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.10,page no:19\n", "velocity of electron in m/s: 59299945.33\n", "momentum of electron in Kgm/s: 5.3963e-23\n", "de Broglie wavelength of electron in angstrom= 0.123\n" ] } ], "source": [ "#cal of velocity of electron,momentum of electron,de Broglie wavelength of electron\n", "#intiation of all variables \n", "#Given that\n", "import math\n", "E = 10. # Energy of electron in KeV\n", "me = 9.1e-31 # Mass of electron in Kg\n", "h = 6.63e-34 # Plank constant\n", "print(\"Example 1.10,page no:19\")\n", "v = math.sqrt(2*E*1.6e-16/me) # Calculation of velocity of moving electron\n", "p = me*v #Calculation of momentum of moving electron\n", "lamda = h/p # calculation of de Broglie wavelength\n", "print(\"velocity of electron in m/s:\"),round(v,2)\n", "print(\"momentum of electron in Kgm/s:\"),round(p,27)\n", "print(\"de Broglie wavelength of electron in angstrom=\"),round(lamda*1e10,3)\n", "# Answers in book are v = 5.93e6 m/s, p = 5.397e-24 kgm/s, lambda = 1.23 angstrom\n", "# Which is due to wrong calculation" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.11;page no:20" ] }, { "cell_type": "code", "execution_count": 10, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.11,page no:20\n", " velocity of neutron in m/s: 3964.072\n", " Kinetic energy of neutron in eV= 0.082\n" ] } ], "source": [ "#cal of velocity and kinetic energy of neutron\n", "#intiation of all variables \n", "#Given that\n", "lamda= 1 # de Broglie wavelength of neutron in angstrom\n", "m = 1.67e-27 # Mass of electron in Kg\n", "h = 6.62e-34 # Plank constant\n", "print(\"Example 1.11,page no:20\")\n", "v = h/(m*lamda*1e-10) # Calculation of velocity of moving neutron\n", "print(\" velocity of neutron in m/s:\"),round(v,3)\n", "E = 1./2.*m*v**2 # Calculation of kinetic energy of moving neutron\n", "print(\" Kinetic energy of neutron in eV=\"),round(E/1.6e-19,3)\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.12;page no:20" ] }, { "cell_type": "code", "execution_count": 12, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.12,page no:20\n", "Wavelength of electron in metres= 2.74e-11\n" ] } ], "source": [ "#cal of de brogle wavelength of electron\n", "#intiation of all variables \n", "#given that\n", "import math\n", "E = 2 # Energy of accelerated electron in KeV\n", "m = 9.1e-31 # Mass of electron in Kg\n", "h = 6.62e-34 # Plank constant\n", "print(\"Example 1.12,page no:20\")\n", "lamda = h/math.sqrt(2*m*E*1e3*1.6e-19) # Calculation of velocity of moving electron\n", "print(\"Wavelength of electron in metres=\"),round(lamda,13)\n", "# Answer in book is 2.74e-12m\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.13;page no:21" ] }, { "cell_type": "code", "execution_count": 13, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.13,page no:21\n", "Wavelength of matter wave in angstrom= 1.48e-05\n" ] } ], "source": [ "#cal of de brogle wavelength of matter wave\n", "#intiation of all variables \n", "#given that\n", "import math\n", "v = 2e8 # speed of moving proton in m/s\n", "c = 3e8 # speed of light in m/s\n", "m = 1.67e-27 # Mass of proton in Kg\n", "h = 6.62e-34 # Plank constant\n", "print(\"Example 1.13,page no:21\")\n", "lamda = h/(m*v/math.sqrt(1-(v/c)**2)) # Calculation of velocity of moving electron\n", "print(\"Wavelength of matter wave in angstrom=\"),round(lamda*1e10,7)\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.14;page no:22" ] }, { "cell_type": "code", "execution_count": 31, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.14,page no:22\n", "Momentum of photon in Kgm/s while Momentum of electron in Kgm/s which are equal: 6.63e-24 6.63e-24\n", "Total Energy of photon in joule while Total Energy of electron in MeV: 1.989e-15 2.42e-17\n", "Ratio of kinetic energies in: 0.0121\n" ] } ], "source": [ "#cal of momentum,total energy and ratio of kinetic energy of photon\n", "#intiation of all variables \n", "#given that\n", "lamda = 1# wavelength in m/s\n", "m_e = 9.1e-31 # Mass of electron in Kg\n", "m_p = 1.67e-27 # Mass of proton in kg\n", "c = 3e8 # speed of light in m/s\n", "h = 6.63e-34 # Plank constant\n", "print(\"Example 1.14,page no:22\")\n", "p_e = h/(lamda*1e-10) # Momentum of electron\n", "p_p = h/(lamda*1e-10) # Momentum of photon\n", "print(\"Momentum of photon in Kgm/s while Momentum of electron in Kgm/s which are equal:\"),round(p_p,26),round(p_e,26)\n", "E_e = p_e**2/(2*m_e) +m_e*c**2 # Total energy of electron\n", "E_e1=(2.42*10**-17)+(m_e*c**2/1.6*10**-19)\n", "E_p = h*c/(lamda*1e-10) # Total energy of photon\n", "print(\"Total Energy of photon in joule while Total Energy of electron in MeV:\"),round(E_p,18),E_e1\n", "K_e = p_e**2/(2*m_e) # Kinetic energy of electron \n", "K_p = h*c/(lamda*1e-10)# Kinetic energy of photon\n", "r_K = K_e/K_p # Ratio of kinetic energies\n", "print(\"Ratio of kinetic energies in:\"),round(r_K,4)\n", "\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.15;page no:24" ] }, { "cell_type": "code", "execution_count": 2, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.15,page no:24\n", "de Broglie wavelength of neutron in angstrom: 0.0573\n" ] } ], "source": [ "#cal of de brogle wavelength of neutron\n", "#intiation of all variables \n", "#given that\n", "import math\n", "e = 25 # Energy of neutron in eV\n", "c = 3e8 # speed of light in m/s\n", "m = 1.67e-27 # Mass of neutron in Kg\n", "h = 6.62e-34 # Plank constant\n", "print(\"Example 1.15,page no:24\")\n", "rest_e = m*c**2/(1e6*1.6e-19)# rest mass energy of neutron in MeV\n", "if e/rest_e < 0.015:\n", " E = e;\n", "else:\n", "\tE = rest_e +e;\n", "lamda = h/(math.sqrt(2*m*e*1.6e-19)) # calculation of de Broglie wavelength\n", "print(\"de Broglie wavelength of neutron in angstrom:\"),round(lamda*1e10,4)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.16;page no:24" ] }, { "cell_type": "code", "execution_count": 14, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.16,page no:24\n", "de Broglie wavelength of neutron in angstrom: 0.00717\n" ] } ], "source": [ "#cal of de brogle wavelength of neutron \n", "#intiation of all variables \n", "#given that\n", "import math\n", "e = 2*1.6e-19 # charge on alpha particle in coulomb\n", "V = 200 # Applied voltage in volts\n", "m = 4*1.67e-27 # Mass of alpha particle in Kg\n", "h = 6.63e-34 # Plank constant\n", "print(\"Example 1.16,page no:24\")\n", "lamda=h/(math.sqrt(2*e*V*m)) # calculation of de Broglie wavelength\n", "print(\"de Broglie wavelength of neutron in angstrom:\"),round(lamda*1e10,5)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.17;page no:25" ] }, { "cell_type": "code", "execution_count": 18, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.17,page no:25\n", "de Broglie wavelength of ball in angstrom: 6.62e-26\n", "de Broglie wavelength of electron in angstrom: 7.27\n" ] } ], "source": [ "#cal of de brogle wavelength of ball and electron\n", "#intiation of all variables \n", "#given that\n", "M = 20 # Mass of ball in Kg\n", "V = 5 # velocity of of ball in m/s\n", "m = 9.1e-31 #Mass of electron in Kg\n", "v = 1e6 # velocity of of electron in m/s\n", "h = 6.62e-34 # Plank constant\n", "print(\"Example 1.17,page no:25\")\n", "lambda_b = h/(M*V) # calculation of de Broglie wavelength for ball\n", "lambda_e = h/(m*v) # calculation of de Broglie wavelength electron\n", "print(\"de Broglie wavelength of ball in angstrom:\"),round(lambda_b*1e10,34)\n", "print(\"de Broglie wavelength of electron in angstrom:\"),round(lambda_e*1e10,2)\n", "# answer in book is 6.62e-22 angstrom for ball\n", "\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.18;page no:26" ] }, { "cell_type": "code", "execution_count": 15, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.18,page no:26\n", "Wavelength of neutron in angstrom: 0.286\n" ] } ], "source": [ "#cal of de brogle wavelength of neutron\n", "#intiation of all variables \n", "#given that\n", "import math\n", "E = 1 # Energy of neutron in eV\n", "m = 1.67e-27 # Mass of neutron in Kg\n", "h = 6.62e-34 # Plank constant\n", "print(\"Example 1.18,page no:26\")\n", "lamda = h/math.sqrt(2*m*E*1.6e-19) # Calculation of velocity of moving electron\n", "print(\"Wavelength of neutron in angstrom:\"),round(lamda*1e10,3)\n", "# Answer in book is 6.62e-22 angstrom\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.19;page no:27" ] }, { "cell_type": "code", "execution_count": 20, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.19,page no:27\n", "Applied voltage on electron in V: 602.0\n" ] } ], "source": [ "#cal of Applied voltage on electron \n", "#intiation of all variables \n", "#given that\n", "lamda = 0.5# wavelength of electron in angstrom\n", "m = 9.1e-31 # Mass of electron in Kg\n", "h = 6.62e-34 # Plank constant\n", "q = 1.6e-19 # charge on electron in coulomb\n", "print(\"Example 1.19,page no:27\")\n", "V = h**2/(2*m*q*(lamda*1e-10)**2) # Calculation of velocity of moving electron\n", "print(\"Applied voltage on electron in V:\"),round(V,1)\n", "# Answer in book is 601.6 Volt\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.21;page no:29" ] }, { "cell_type": "code", "execution_count": 21, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.21,page no:29\n", "Wavelength of neutron at degree Celsius in angstrom: 1.43\n" ] } ], "source": [ "#cal of wavelength of neutron\n", "#intiation of all variables \n", "#given that\n", "import math\n", "k = 8.6e-5 # Boltzmann constant\n", "t = 37 # Temperature in degree Celsius\n", "h = 6.62e-34 # Plank constant\n", "m = 1.67e-27 # Mass of neutron\n", "print(\"Example 1.21,page no:29\")\n", "lamda = h/math.sqrt(3*m*(k*1.6e-19)*(t+273))# Calculation of wavelength\n", "print(\"Wavelength of neutron at degree Celsius in angstrom:\"),round(lamda*1e10,2)\n", "\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.22;page no:29" ] }, { "cell_type": "code", "execution_count": 22, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.22,page no:29\n", "Wavelength of helium at degree Celsius in angstrom: 0.727\n" ] } ], "source": [ "#cal of wavelength of helium\n", "#intiation of all variables \n", "#given that\n", "import math\n", "k = 8.6e-5 # Boltzmann constant\n", "t = 27 # Temperature in degree Celsius\n", "h = 6.62e-34 # Plank constant\n", "m = 6.7e-27 # Mass of helium atom\n", "print(\"Example 1.22,page no:29\")\n", "lamda = h/math.sqrt(3*m*(k*1.6e-19)*(t+273))# Calculation of wavelength\n", "print(\"Wavelength of helium at degree Celsius in angstrom:\"),round(lamda*1e10,3)\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.23;page no:30" ] }, { "cell_type": "code", "execution_count": 17, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.23,page no:30\n", "lamda= 8.67e-11\n", "D/2*x= 0.05\n", "tan(theta)= 0.05\n", "Interatomic spacing of crystal in angstrom: 8.67\n" ] } ], "source": [ "#cal of Interatomic spacing of crystal\n", "#intiation of all variables \n", "#given that\n", "import math\n", "E = 200. # energy of electrons in eV\n", "x = 20. # distance of screen in cm\n", "D = 2. # diameter of ring in cm\n", "h = 6.62e-34 # Plank constant\n", "m = 9.1e-31 # Mass of electron in kg\n", "print(\"Example 1.23,page no:30\")\n", "lamda= h/math.sqrt(2*m*E*1.6e-19) # Calculation of wavelength\n", "print(\"lamda=\"),round(lamda,13)\n", "print(\"D/2*x=\"),D/(2*x)\n", "p=D/(2*x)\n", "print(\"tan(theta)=\"),p\n", "d = lamda/(2*p)# calculation of interatomic spacing of crystal\n", "print(\"Interatomic spacing of crystal in angstrom:\"),round(d*1e10,2)\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.24;page no:31" ] }, { "cell_type": "code", "execution_count": 21, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.24,page no:31\n", "Velocity of electron in ground state in M/s= 2.31\n" ] } ], "source": [ "#cal of velocity of electron \n", "#intiation of all variables \n", "#given that\n", "r = 0.5 # Bohr radius of hydrogen in angstrom\n", "m = 9.1e-31 # Mass of neutron in Kg\n", "h = 6.6e-34 # Plank constant\n", "print(\"Example 1.24,page no:31\")\n", "v = h/(2*3.14*r*1e-10*m) # velocity of electron in ground state\n", "print(\"Velocity of electron in ground state in M/s=\"),round(v/10**6,2)\n", "# Answer in book is 2.31e6 m/s\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.25;page no:32" ] }, { "cell_type": "code", "execution_count": 25, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.25,page no:32\n", "Velocity of electron in ground state in m/s: 1237.0\n" ] } ], "source": [ "#cal of Velocity of electron in ground state\n", "#intiation of all variables \n", "#given that\n", "lamda = 5890 # wavelength of yellow radiation in angstrom\n", "m = 9.1e-31 # Mass of neutron in Kg\n", "h = 6.63e-34 # Plank constant\n", "print(\"Example 1.25,page no:32\")\n", "v = h/(lamda*1e-10*m) # velocity of electron in ground state\n", "print(\"Velocity of electron in ground state in m/s:\"),round(v,1)\n", "# Answer in book is 1.24e3 m/s\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.26;page no:33" ] }, { "cell_type": "code", "execution_count": 26, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.26,page no:33\n", "Velocity of neutron in m/s: 1985.0\n", "Kinetic energy of neutron in eV: 0.021\n" ] } ], "source": [ "#cal of Velocity and kinetic energy of neutron\n", "#intiation of all variables \n", "#given that\n", "lamda = 2 # wavelength of neutron in angstrom\n", "m = 1.67e-27 # Mass of neutron in Kg\n", "h = 6.63e-34 # Plank constant\n", "print(\"Example 1.26,page no:33\")\n", "v = h/(lamda*1e-10*m) # velocity of neutron\n", "k = 0.5*m*v**2 # Kinetic energy of neutron\n", "print(\"Velocity of neutron in m/s:\"),round(v,1)\n", "print(\"Kinetic energy of neutron in eV:\"),round(k/1.6e-19,3)\n", "# Answer in book is 0.021eV\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.29;page no:36" ] }, { "cell_type": "code", "execution_count": 22, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.29,page no:36\n", "theta 72.6\n", "theta1= 56.84\n", "For first order, sin(theta) in For second order sin(theta) must be which is not possible for any value of angle.So no maxima occur for higher orders: 1.91\n" ] } ], "source": [ "#cal of theta and theta1 \n", "#intiation of all variables \n", "#given that\n", "import math\n", "v1 = 50 # Previous applied voltage\n", "v2 = 65 # final applied voltage\n", "k = 12.28 \n", "d = 0.91 # Spacing in a crystal in angstrom\n", "print(\"Example 1.29,page no:36\")\n", "lamda = k/math.sqrt(v1)\n", "theta= math.asin(lamda/(2*d))# Angel for initial applied voltage\n", "lamda1 = k/math.sqrt(v2)# wavelength for final applied voltage\n", "theta1 = math.asin(lamda1/(2*d))# Angel for final applied voltage\n", "#print(\"lamda1/1.82=\"),math.asin(lamda1/1.82)\n", "print(\"theta\"),round(theta*180/3.14,1)\n", "print(\"theta1=\"),round(theta1*180/3.14,2)\n", "print(\"For first order, sin(theta) in For second order sin(theta) must be which is not possible for any value of angle.So no maxima occur for higher orders:\"),round(2*math.sin(theta),2)\n", "#print(\"Angle of diffraction for first order of beam is degree at Volts:\"),round((math.theta1*180/math.pi),2)\n", "# Answer in book is 57.14 degree" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.30;page no:45" ] }, { "cell_type": "code", "execution_count": 28, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.30,page no:45\n", "Group velocity of seawater waves in m/s: 16.29\n" ] } ], "source": [ "#cal of Group velocity of seawater waves\n", "#intiation of all variables \n", "#given that\n", "import math\n", "lamda = 680 # Wavelength in m\n", "g = 9.8 #Acceleration due to gravity\n", "print(\"Example 1.30,page no:45\")\n", "v_g = 0.5*math.sqrt(g*lamda/(2*3.14)) # Calculation of group velocity\n", "print(\"Group velocity of seawater waves in m/s:\"),round(v_g,2)\n", "# Answer in book is 16.29 m/s\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.32;page no:47" ] }, { "cell_type": "code", "execution_count": 29, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.32,page no:47\n", "Group velocity of de Broglie waves is c : 0.9966\n", " phase velocity of de Broglie waves is c 1.0034\n" ] } ], "source": [ "#cal of group and phase velocity of de brogle waves \n", "#intiation of all variables \n", "#given that\n", "import math\n", "lamda = 2e-13 # de Broglie wavelength of an electron in m\n", "c = 3e8 # Speed of light in m/s\n", "m = 9.1e-31 # Mass of electron in Kg\n", "h = 6.63e-34 # Plank constant\n", "print(\"Example 1.32,page no:47\")\n", "E = h*c/(lamda*1.6e-19) \n", "E_rest = m*c**2/(1.6e-19) # Calculation of rest mass energy\n", "E_total = math.sqrt(E**2+E_rest**2) # Total energy in eV\n", "v_g = c*math.sqrt(1-(E_rest/E_total)**2) # Group velocity\n", "v_p = c**2/v_g # Phase velocity\n", "print(\"Group velocity of de Broglie waves is c :\"),round(v_g/c,4)\n", "print(\" phase velocity of de Broglie waves is c\"),round(v_p/c,4)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## example 1.33;page no:48" ] }, { "cell_type": "code", "execution_count": 23, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Example 1.33,page no:48\n", "Kinetic energy of electron in KeV: 293.33\n", "Group velocity of de Broglie waves is c in m/s: 0.7719\n", "phase velocity of de Broglie waves is c in m/s: 1.295\n" ] } ], "source": [ "#cal of Kinetic energy of electron,group velocity and phase velocity of de Broglie waves\n", "#intiation of all variables \n", "#given that\n", "import math\n", "lamda = 2.e-12 # de Broglie wavelength of an electron in m\n", "c = 3.e8 # Speed of light in m/s\n", "m = 9.1e-31 # Mass of electron in Kg\n", "h = 6.63e-34 # Plank constant\n", "print(\"Example 1.33,page no:48\")\n", "E = h*c/(lamda*1.6e-19) # Energy due to momentum\n", "E_rest = m*c**2/(1.6e-19) # Calculation of rest mass energy\n", "E_total = math.sqrt(E**2+E_rest**2) # Total energy in eV\n", "KE = E_total - E_rest # Kinetic energy\n", "v_g = c*math.sqrt(1-(E_rest/E_total)**2) # Group velocity\n", "v_p = c**2/v_g # Phase velocity\n", "print(\"Kinetic energy of electron in KeV:\"),round(KE/1000,2)\n", "print(\"Group velocity of de Broglie waves is c in m/s:\"),round(v_g/c,4)\n", "print(\"phase velocity of de Broglie waves is c in m/s:\"),round(v_p/c,3)\n", "# Answer in book is v_g = 0.6035c & v_p = 1.657c\n" ] } ], "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": "2.7.10" } }, "nbformat": 4, "nbformat_minor": 0 }