{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# Chapter 2: Relativity II" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 2.1: Momentum_of_an_electron.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// Scilab code Ex2.1: Pg.44 (2005)\n", "clc; clear;\n", "c = 3e08; // Velocity of light, m/s\n", "u = 0.750*c; // Velocity of electron, m/s\n", "m = 9.11e-31; // Rest mass of electron, kg\n", "p_r = m*u/(sqrt(1 - (u/c)^2)); // Relativistic momentum of electron, kgm/s\n", "p = m*u; // Classical momentum of electron, kg-m/s\n", "printf('\nThe relativistic momentum of electron = %4.2fe-22 kg-m/s', p_r*1e+22);\n", "printf('\nThe classical momentum of electron = %4.2fe-22 kg-m/s', p*1e+22);\n", "printf('\nThe relativistic result is 50 percent greater than the classical result.');\n", "\n", "//Result\n", "// The relativistic momentum of electron = 3.10e-22 kg-m/s\n", "// The classical momentum of electron = 2.05e-22 kg-m/s\n", "// The relativistic result is 50 percent greater than the classical result." ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 2.3: Energy_of_a_speedy_electron.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// Scilab code Ex2.3: Pg.47 (2005)\n", "clc; clear;\n", "c = 3e+08; // Velocity of light, m/s\n", "u = 0.85*c; // Velocity of electron, m/s\n", "E_0 = 0.511; // Rest energy of electron, MeV\n", "E = E_0/(sqrt(1-(u/c)^2)); // Total energy of electron, MeV\n", "K = E - E_0; // Kinetic energy of electron, MeV\n", "printf('\nThe total energy of electron = %5.3f MeV', E);\n", "printf('\nThe kinetic energy of electron = %5.3f MeV', K);\n", "\n", "// Result\n", "// The total energy of electron = 0.970 MeV\n", "// The kinetic energy of electron = 0.459 MeV" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 2.4: Energy_of_a_speedy_proton.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// Scilab code Ex2.4: Pg.47 (2005)\n", "clc; clear;\n", "c = 3e+08; // Velocity of light, m/s\n", "u = 0.85*c; // Velocity of electron, m/s\n", "m_p = 1.67e-27; // Rest mass of proton, kg\n", "\n", "// Part (a)\n", "E_o = m_p*c^2/1.602e-019; // Rest energy of proton, MeV\n", "printf('\nRest energy of proton = %3d MeV', E_o/1e+06);\n", "\n", "// Part (b)\n", "// Since given that E = 3*E_o = (3*m_p*c^2)/sqrt(1-(u/c)^2), solving for u\n", "u = sqrt(8/9)*c; // Velocity of proton, m/s\n", "printf('\nVelocity of proton = %4.2fe+08 m/s', u*1e-08);\n", "\n", "// Part (c)\n", "// Since K = E - m_p*(c^2) = 3*m_p*(c^2) - m_p*(c^2) = 2*m_p*(c^2)\n", "K = 2*E_o; // Kinetic energy of proton, MeV\n", "printf('\nThe kinetic energy of proton = %4d MeV', K*1e-06);\n", "\n", "// Part (d)\n", "p = sqrt(8)*(E_o);\n", "printf('\nThe momentum of proton = %4d MeV/c', p*1e-06);\n", "\n", "// Result\n", "// Rest energy of proton = 938 MeV\n", "// Velocity of proton = 2.83e+08 m/s\n", "// The kinetic energy of proton = 1876 MeV\n", "// The momentum of proton = 2653 MeV/c " ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 2.5: Increase_in_mass_of_colliding_balls.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// Scilab code Ex2.5: Pg.49 (2005)\n", "clc; clear;\n", "u = 450; // Velocity ofeach ball, m/s\n", "m = 5; // Mass of each ball, kg\n", "c = 3e+08; // Velocity of light, m/s\n", "// Since (u/c)^2 << 1, therefore, substituting 1/sqrt(1 - (u/c)^2) = 1 + (1/2)*(u/c)^2\n", "delta_M = m*(u/c)^2; // Increase in the mass of balls, kg\n", "printf('\nIncrease in the mass of the balls = %3.1fe-11 kg', delta_M*1e+11);\n", "\n", "// Result\n", "// Increase in the mass of the balls = 1.1e-11 kg" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 2.7: A_Fission_Reaction.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// Scilab code Ex2.7: Pg.50 (2005)\n", "clc; clear;\n", "u = 1.660e-27; // Atomic mass unit\n", "M_U = 236.045563; // Atomic mass of Uranium, u\n", "M_Rb = 89.914811; // Atomic mass of Rubidium, u\n", "M_Cs = 142.927220; // Atomic mass of Caesium, u\n", "m_n = 1.008665; // Mass of neutons, u\n", "\n", "// Part (a)\n", "printf('\nU(92,235) --> Rb(37,90) + Cs(55,143) + 3n(0,1)');\n", "printf('\nSo three neutrons are produced per fission.\n');\n", "\n", "// Part (b)\n", "delta_M = (M_U - (M_Rb + M_Cs + 3*m_n))*u; // Combined mass of all products, kg\n", "printf('\nCombined mass of all products = %6.4fe-28 kg\n', delta_M*1e+28);\n", "\n", "// Part (c)\n", "// For simplification let velocity of light = 1 m/s\n", "c = 1; // Velocity of light, m/s\n", "// Since 1u = 931.5 MeV/(c^2), therefore\n", "Q = (delta_M/u)*931.5*(c^2); // Energy given out per fission event, MeV\n", "printf('\nEnergy given out per fission event = %5.1f MeV\n', Q);\n", "\n", "// Part (d)\n", "N = ((6.02e23)*1000)/236; // Number of nuclei present\n", "efficiency = 0.40;\n", "E = efficiency*N*Q*(4.45e-20); // Total energy released, kWh\n", "printf('\nTotal energy released = %4.2fe+06 kWh\n', E*1e-06);\n", "\n", "printf('\nThis amount of energy will keep a 100-W lightbulb burning for %d years', E*1000/(100*24*365));\n", "\n", "// Result\n", "// U(92,235) --> Rb(37,90) + Cs(55,143) + 3n(0,1)\n", "// So three neutrons are produced per fission.\n", "// Combined mass of all products = 2.9471e-28 kg\n", "// Energy given out per fission event = 165.4 MeV\n", "// Total energy released = 7.51e+06 kWh\n", "// This amount of energy will keep a 100-W lightbulb burning for 8571 years " ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 2.8: Energy_conservation.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// Scilab code Ex2.8: Pg.52 (2005)\n", "clc; clear;\n", "\n", "// Part (a)\n", "// Since 1 eV = 1.6e-19 J, therefore 3 eV = 3*1.6e-19\n", "BE = 3*1.6e-19; // Binding energy of water, J\n", "c = 3e+08; // Velocity of light, m/s\n", "delta_m = BE/(c^2); // Mass difference of water molecule & it constituents, kg\n", "printf('\nMass difference of water molecule & it constituents = %3.1fe-36 kg', delta_m*1e+36);\n", "\n", "// Part (b)\n", "M = 3.0e-26; // Mass of water molecule, kg\n", "M_f = delta_m/M; // Fractional loss of mass per molecule\n", "printf('\nThe fractional loss of mass per molecule = %3.1fe-10', M_f*1e+10);\n", "\n", "// Part (c)\n", "E = M_f*(c^2); // Energy released when 1 g of water is formed, kJ\n", "printf('\nEnergy released when 1 g of water is formed = %2.0f kJ', E*1e-06);\n", "\n", "// Result\n", "// Mass difference of water molecule & it constituents = 5.3e-36 kg\n", "// The fractional loss of mass per molecule = 1.8e-10\n", "// Energy released when 1 g of water is formed = 16 kJ" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 2.9: Mass_of_Pio.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// Scilab code Ex2.9: Pg.53 (2005)\n", "clc; clear;\n", "K_mu = 4.6; // Kinetic energy of muon, MeV\n", "// For convinience let m_mew*(c^2) = E_mew\n", "E_mu = 106; // Energy of muon, MeV\n", "E_pion = sqrt((E_mu^2) + (K_mu^2) + (2*K_mu*E_mu)) + sqrt((K_mu^2) + (2*K_mu*E_mu));\n", "m_pion = E_pion; // Mass of pion, MeV/(c^2)\n", "printf('\nMass of Pion = %3.0f MeV/(c^2)', m_pion);\n", "\n", "// Result\n", "// Mass of Pion = 142 MeV/(c^2)" ] } ], "metadata": { "kernelspec": { "display_name": "Scilab", "language": "scilab", "name": "scilab" }, "language_info": { "file_extension": ".sce", "help_links": [ { "text": "MetaKernel Magics", "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md" } ], "mimetype": "text/x-octave", "name": "scilab", "version": "0.7.1" } }, "nbformat": 4, "nbformat_minor": 0 }