{ "metadata": { "name": "" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 11: Theory of Relativity" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.5, Page 11.19" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "# Given \n", "x = 100 # in meter\n", "y = 10 # in meter\n", "z = 5 # in meter\n", "t = 1e-4 # in sec\n", "# coordinates of point in frame F\n", "v = 2.7e8 # velocity of frame F_ w.r.t. frame F in m/sed\n", "c=3e8 # speed of light in m/sec\n", "\n", "#Calculations\n", "# according to Galilean transformation\n", "x__ = x-v*t\n", "y__=y\n", "z__=z\n", "t__=t\n", "# according to Lorentz transformation\n", "x_ = (x-v*t)/sqrt(1-(v/c)**2)\n", "y_=y\n", "z_=z\n", "t_=(t-(v*x/c**2))/sqrt(1-(v/c)**2)\n", "\n", "#Results\n", "print \"Coordinate of the event in reference frame F_ using \\n(a)Galilean transformation-x=%.f m, y=%.f m, z = %.f m, t = %.e sec\"%(x__,y__,z__,t__) \n", "print \"(b)Lorentz transformation-x=%.f m,y =%.f m, z = %.f m, t=%.e sec \"%(x_,y_,z_,t_)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Coordinate of the event in reference frame F_ using \n", "(a)Galilean transformation-x=-26900 m, y=10 m, z = 5 m, t = 1e-04 sec\n", "(b)Lorentz transformation-x=-61713 m,y =10 m, z = 5 m, t=2e-04 sec \n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.6, Page 11.19" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "r = 4 # ratio of mass of particle to the rest mass\n", "\n", "#Calculations\n", "v = 3e8 * sqrt(1 - (1 / r)**2)\n", "\n", "#Result\n", "print \"Speed of particle is %.e meter/sec\"%v" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Speed of particle is 3e+08 meter/sec\n" ] } ], "prompt_number": 12 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.7, Page 11.20" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "r = 1.2 # ratio of mass of particle to the rest mass\n", "\n", "#Calculations\n", "v = 3e8 * sqrt(1 - (1 / r)**2)\n", "\n", "#Results\n", "print \"Speed of particle is %.3f c\"%(v/3e8)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Speed of particle is 0.553 c\n" ] } ], "prompt_number": 14 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.9, Page 11.20" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "# Given \n", "E = 2 # kinetic energy of electron in Mev\n", "\n", "#Calculations\n", "v = 3e8 * sqrt(1 - (1 / (1 + (1.6e-19 * 2e6) / (9.1e-31 * 3e8**2)))**2)\n", "m = (9.1e-31) / sqrt(1 - (v / 3e8)**2)\n", "\n", "#Results\n", "print \"Speed of electron is %.2f c\\nMass of electron is %.2e kg\"%(v/3e8,m)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Speed of electron is 0.98 c\n", "Mass of electron is 4.47e-30 kg\n" ] } ], "prompt_number": 16 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.11, Page 11.21" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "# Given \n", "r = 2.25 # ratio of mass of particle to the rest mass\n", "\n", "#Calculations\n", "v = 3e8 * sqrt(1 - (1 / r)**2)\n", "\n", "#Result\n", "print \"Speed of particle is %.2e meter/sec\"%v" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Speed of particle is 2.69e+08 meter/sec\n" ] } ], "prompt_number": 18 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.12, Page 11.22" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "r = 2. # ratio of kinetic energy of body to its rest mass\n", "\n", "#Calculations\n", "v = 3e8 * sqrt(1 - (1 / (r + 1))**2)\n", "\n", "#Result\n", "print \"Velocity of particle is %.2f c\"%(v/3e8)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Velocity of particle is 0.94 c\n" ] } ], "prompt_number": 22 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.13, Page 11.22" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "r = 11. # ratio of mass of particle to the rest mass of electron\n", "\n", "#Calculations\n", "KE = (r - 1) * 9.1e-31 * 3e8**2 / (1.6e-19)\n", "m = 3e8 * sqrt(1 - (1 / r)**2) * 9.1e-31 * 11\n", "\n", "#Result\n", "print \"Kinetic energy of electron is %.1f MeV\\nMomentum of particle is %.2e N-sec\"%(KE/1e6,m)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Kinetic energy of electron is 5.1 MeV\n", "Momentum of particle is 2.99e-21 N-sec\n" ] } ], "prompt_number": 24 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.14, Page 11.23" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "m = 1.67e-27 # mass of electron in kg\n", "m_ = 9.1e-31 # rest mass of electron in kg\n", "\n", "#Calculations\n", "v = 3e8 * sqrt(1 - (m_ / m)**2)\n", "\n", "#Result\n", "print \"Velocity of electron is %.3e meter/sec\"%v" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Velocity of electron is 3.000e+08 meter/sec\n" ] } ], "prompt_number": 30 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.15, Page 11.23" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "E = 0.1 # kinetic speed of electron in Mev\n", "\n", "#Calculations\n", "v_ = sqrt(2 * (E * 1.6e-13) / 9.1e-31)\n", "v = 3e8 * sqrt(1 - (1 / (1 + (1.6e-13 * E) / (9.1e-31 * 3e8**2)))**2)\n", "\n", "#Results\n", "print \"Speed according to classical mechanics is %.2e meter/sec\\nSpeed according to relativistic mechanics is %.2e meter/sec\"%(v_,v)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Speed according to classical mechanics is 1.88e+08 meter/sec\n", "Speed according to relativistic mechanics is 1.64e+08 meter/sec\n" ] } ], "prompt_number": 33 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.17, Page 11.24" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "r1 = 3. # ratio of kinetic energy of body to its rest mass in first case\n", "r2 = 1. # ratio of kinetic energy of body to its rest mass in second case\n", "\n", "#Calculations\n", "v1 = 3e8 * sqrt(1 - (1 / (r1 + 1))**2)\n", "v2 = 3e8 * sqrt(1 - (1 / (r2 + 1))**2)\n", "\n", "#Results\n", "print \"Velocity of particle if kinetic energy is %d times of rest mass energy is %.2e meter/sec\\nVelocity of particle if kinetic energy is %.1e times of rest mass energy is %e meter/sec\"%(r1,v1,r2,v2)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Velocity of particle if kinetic energy is 3 times of rest mass energy is 2.90e+08 meter/sec\n", "Velocity of particle if kinetic energy is 1.0e+00 times of rest mass energy is 2.598076e+08 meter/sec\n" ] } ], "prompt_number": 39 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.19, Page 11.25" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "E = 1.5 # kinetic energy of electron in Mev\n", "\n", "#Calculations\n", "v = 3e8 * sqrt(1 - (1 / (1 + (1.6e-19 * 2e6) / (9.1e-31 * 3e8**2)))**2)\n", "m = (E * 1.6e-13 / (3e8)**2) + 9.1e-31\n", "\n", "#Results\n", "print \"Speed of electron is %.2e meter/sec\\nMass of electron is %.1e kg\"%(v,m)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Speed of electron is 2.94e+08 meter/sec\n", "Mass of electron is 3.6e-30 kg\n" ] } ], "prompt_number": 40 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.20, Page 11.26" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "# Given \n", "r = 3. / 2 # ratio of mass of metre stick to the rest mass of metre stick\n", "\n", "#Calculations\n", "l = 1 * (1. / r)\n", "\n", "#Result\n", "print \"Length of meter stick is %.2f meter if mass is %.2f times of its rest mass\"%(l,r)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Length of meter stick is 0.67 meter if mass is 1.50 times of its rest mass\n" ] } ], "prompt_number": 43 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.21, Page 11.26" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "# Given \n", "r = 1. / 2 # ratio of area of circular lamina in frame S_ to the ratio of area of circular lamina in frame S\n", "\n", "#Calculations\n", "v = 3e8 * sqrt(1 - r**2)\n", "\n", "#Result\n", "print \"Velocity of frame S_ w.r.t. frame S is %.1e meter/sec\"%v" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Velocity of frame S_ w.r.t. frame S is 2.6e+08 meter/sec\n" ] } ], "prompt_number": 45 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.22, Page 11.27" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import * \n", "# Given \n", "t = 1 # lose in time in an hour in minute\n", "\n", "#Calculations\n", "v = 3e8 * sqrt(1 - ((60. - t) / 60)**2)\n", "\n", "#Result\n", "print \"Speed of clock is %.2e meter/sec\"%v" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Speed of clock is 5.45e+07 meter/sec\n" ] } ], "prompt_number": 47 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.23, Page 11.27" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "# Given \n", "t_ = 2.5e-8 # proper life of pi+ mesons in sec\n", "v = 2.4e8 # velocity of beam of mesons in m/sec\n", "r = 1. / exp(2) # ratio of final flux to initial flux of the meson beam\n", "\n", "#Calculations\n", "t = t_ / sqrt(1 - (v / 3e8)**2)\n", "T = t * log(1. / r)\n", "d = T * v\n", "\n", "#Result\n", "print \"Distance travel by the beam is %.2f meter\"%d" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Distance travel by the beam is 20.00 meter\n" ] } ], "prompt_number": 48 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.24, Page 11.27" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "# Given \n", "v = 1.8e8 # velocity of space ship away from the earth in m/sec\n", "v1 = 2.1e8 # velocity of rocket w.r.t. space ship away from the earth in first case in m/sec\n", "v2 = -2.1e8 # velocity of rocket w.r.t. space ship away from the earth in second case in m/sec\n", "\n", "#Calculations\n", "u1 = (v1 + v) / (1 + ((v1 * v) / (3e8)**2))\n", "u2 = (v2 + v) / (1 + ((v2 * v) / (3e8)**2))\n", "\n", "#Results\n", "print \"Velocity of rocket w.r.t. earth in first case = %.2f c away from the earth\\nVelocity of rocket w.r.t. earth in second case = %.2f c away from the earth \"%(u1/3e8,u2/3e8)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Velocity of rocket w.r.t. earth in first case = 0.92 c away from the earth\n", "Velocity of rocket w.r.t. earth in second case = -0.17 c away from the earth \n" ] } ], "prompt_number": 49 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.25, Page 11.28" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "l = 1 # length of the rod in meter\n", "v = 1.8e8 # speed of rod along its length in meter/sec\n", "\n", "#Calculations\n", "L = l * sqrt(1- (v / 3e8)**2)\n", "\n", "#Result\n", "print \"Length as it appear to the observer is %.1f meter\"%L" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Length as it appear to the observer is 0.8 meter\n" ] } ], "prompt_number": 50 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.26, Page 11.28" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "l = 2 # length of the rod in meter\n", "v = 2.7e8 # speed of rod along its length in meter/sec\n", "\n", "#Calculations\n", "L = l * sqrt(1- (v / 3e8)**2)\n", "\n", "#Result\n", "print \"Length as it appear to the observer is %.3f meter\"%L" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Length as it appear to the observer is 0.872 meter\n" ] } ], "prompt_number": 51 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.27, Page 11.28" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "l = 100. # consider the length of the rod in meter\n", "v = 2.4e8 # speed of rod in meter/sec\n", "theta = pi / 3 # direction of velocity of rod along its length in radian\n", "\n", "#Calculations\n", "Lx = l * cos(theta)\n", "Ly = l * sin(theta)\n", "L_x = Lx * sqrt(1 - (v / 3e8)**2)\n", "L_y = Ly \n", "L = sqrt(L_x**2 + L_y**2)\n", "p_l = ((l - L) / l) * 100 \n", "\n", "#Result\n", "print \"Percentage length contraction is %.1f percent\"%p_l" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Percentage length contraction is 8.3 percent\n" ] } ], "prompt_number": 52 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.28, Page 11.29" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "# Given \n", "r = 0.5 # ratio of length of rod when it is in motion to the length of the rod when it is in rest \n", "\n", "#Calculations\n", "v = 3e8 * sqrt(1 - r**2)\n", "\n", "#Result\n", "print \"Speed of the rod relative to observer is %.3f c\"%(v/3e8)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Speed of the rod relative to observer is 0.866 c\n" ] } ], "prompt_number": 53 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.29, Page 11.29" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "l = 5 # length of the rod in meter\n", "v = 1.8e8 # speed of rod in meter/sec\n", "theta = pi / 6 # direction of velocity of rod along its length in radian\n", "\n", "#Calculations\n", "Lx = l * cos(theta)\n", "Ly = l * sin(theta)\n", "L_x = Lx * sqrt(1 - (v / 3e8)**2)\n", "L_y = Ly \n", "L = sqrt(L_x**2 + L_y**2)\n", "orientation = atan(L_y / L_x) * (180 / pi)\n", "\n", "#Results\n", "print \"Length of the rod in moving frame is %.2f meter\\nOrientation of the rod is %.2f degree\"%(L,orientation)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Length of the rod in moving frame is 4.27 meter\n", "Orientation of the rod is 35.82 degree\n" ] } ], "prompt_number": 55 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.30, Page 11.30" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "T = 17.8e-9 # half-life of prticle at rest in sec\n", "v = 2.4e8 # speed of particle in meter/sec\n", "\n", "#Calculations\n", "t = T / (sqrt(1 - (v / 3e8)**2))\n", "\n", "#Result\n", "print \"New half-life of particle is %.2f nanosec\"%(t/1e-9)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "New half-life of particle is 29.67 nanosec\n" ] } ], "prompt_number": 56 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.31, Page 11.30" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "T = 24 # no. of hours in a day\n", "v = 1e8 # speed of spaceship in meter/sec\n", "\n", "#Calculations\n", "t = T * (sqrt(1 - (v / 3e8)**2))\n", "T_ = T - t\n", "m=(T_-1)*60\n", "s=(m-22)*60\n", "\n", "#Result\n", "print \"Time lost per day is %d hours %d minute %d sec\"%(T_,m,s)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Time lost per day is 1 hours 22 minute 21 sec\n" ] } ], "prompt_number": 58 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.32, Page 11.30" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "T = 4. # no. of year when rocket is moving corresponding to one year \n", "\n", "#Calculations\n", "v = 3e8 * sqrt(1 - (1 / T)**2)\n", "\n", "#Result\n", "print \"Speed of rocket is %.2f c\"%(v/3e8)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Speed of rocket is 0.97 c\n" ] } ], "prompt_number": 60 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.33, Page 11.31" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "d = 4 # distance of star from the earth in light years\n", "v = 3e8 * sqrt(0.9999) # speed of rocket in meter/sec\n", "\n", "#Calculations\n", "t = (2 * d * 3e8) / v\n", "T_ = t * sqrt(1 - (v / 3e8)**2)\n", "\n", "#Result\n", "print \"Time taken by the rocket is %.2f year\"%T_" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Time taken by the rocket is 0.08 year\n" ] } ], "prompt_number": 61 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.34, Page 11.31" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "t = 2e-7 # life time of particle when it is moving in sec\n", "v = 2.8e8 # speed of particle in meter/sec\n", "\n", "#Calculations\n", "T_ = t * sqrt(1 - (v / 3e8)**2)\n", "\n", "#Result\n", "print \"Proper life time of particle is %.2e sec\"%T_" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Proper life time of particle is 7.18e-08 sec\n" ] } ], "prompt_number": 62 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.35, Page 11.31" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "# Given \n", "v1 = 2.7e8 # velocity of first electron beam in meter/sec\n", "v2 = -2.7e8 # velocity of second electron beam in meter/sec\n", "\n", "#Calculations\n", "u = v1 - v2\n", "u_ = (v1 - v2) / (1 - (v1 * v2) / (3e8)**2)\n", "\n", "#Results\n", "print \"Velocity of electrons beam w.r.t. another electron beam according to Newtonian mechanics is %.1f c\\nVelocity of electrons beam measured by the observer moving with other electron beam = %.2f c\"%(u/3e8,u_/3e8)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Velocity of electrons beam w.r.t. another electron beam according to Newtonian mechanics is 1.8 c\n", "Velocity of electrons beam measured by the observer moving with other electron beam = 0.99 c\n" ] } ], "prompt_number": 63 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.37, Page 11.32" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "# Given \n", "E = 900 # total relativistic energy of proton in Mev\n", "m = 1.63-27 # rest mass of proton in kg\n", "c = 3e8 # velocity of photon in meter/sec\n", "\n", "#Calculations\n", "m_ = (E * 1.6e-13) / (c)**2\n", "\n", "#Results\n", "print \"Relativistic mass of proton is %.2e kg\\nHere relativistic mass is same as rest mass\\n hence proton is at rest and speed and kinetic energy of proton will be zero\"%(m_)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Relativistic mass of proton is 1.60e-27 kg\n", "Here relativistic mass is same as rest mass\n", " hence proton is at rest and speed and kinetic energy of proton will be zero\n" ] } ], "prompt_number": 64 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.38, Page 11.32" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "# Given \n", "E = 5.4e6 # energy liberates during dynamite explosion in J/kg\n", "c = 3e8 # velocity of photon in meter/sec\n", "\n", "#Calculations\n", "E_ = 1 * c**2 # energy liberated by 1 kg content in J\n", "f = E / E_\n", "\n", "#Result\n", "print \"Fraction of total energy content in it is %.1e per kg\"%f" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Fraction of total energy content in it is 6.0e-11 per kg\n" ] } ], "prompt_number": 65 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.39, Page 11.32" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import * \n", "# Given \n", "k = 1.02 # kinetic energy of electron in Mev\n", "E_ = 0.51 # rest mass energy of electron in Mev\n", "c = 3e8 # velocity of photon in meter/sec\n", "\n", "#Calculations\n", "E = k + E_\n", "v = c * sqrt(1 - (E_ / E)**2)\n", "\n", "#Result\n", "print \"Speed of the electron is %.2e meter/sec\"%v" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Speed of the electron is 2.83e+08 meter/sec\n" ] } ], "prompt_number": 66 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.40, Page 11.33" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import *\n", "\n", "# Given \n", "E = 1400 # solar energy receives by the earth in W/square meter\n", "d = 1.5e11 # distance between earth and the sun in meter\n", "c = 3e8 # velocity of photon in meter/sec\n", "\n", "#Calculations\n", "E_ = 4 * pi * d**2 * E\n", "m = E_ / c**2\n", "\n", "#Result\n", "print \"Rate of decrement of mass of the sun is %.2e kg/sec\"%m" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Rate of decrement of mass of the sun is 4.40e+09 kg/sec\n" ] } ], "prompt_number": 67 } ], "metadata": {} } ] }