{ "metadata": { "name": "chapter 17.ipynb" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 17:Collision of Elastic Bodies" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 17.1,Page No.650" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of Variables\n", "\n", "m1=1 #Kg #MAss of ball A\n", "u1=2 #m/s #Initial velocity of ball A\n", "v1=0 #Final velocity of ball A\n", "\n", "#Ball-2\n", "m2=2 #kg #mass\n", "u2=0 #m/s #Initial velocity\n", "\n", "#Calculation\n", "\n", "#Total Initial momentum\n", "V1=m1*u1+m2*u2 #kg*m/s\n", "\n", "#Total Initial momentum\n", "#V2=m1*v1+m2*u2 #kg*m/s\n", "\n", "#Final velocity of ball B\n", "v2=V1*2**-1 #m/s\n", "\n", "#Coefficient of restitution\n", "e=(v2-v1)*(u1-u2)**-1 \n", "\n", "#Result\n", "print\"Final velocity of ball B is\",round(v2,2),\"m/s\"\n", "print\"Coefficient of restitution is\",round(e,2)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Final velocity of ball B is 1.0 m/s\n", "Coefficient of restitution is 0.5\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 17.2,Page No.650" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of Variables\n", "\n", "#first body\n", "m1=50 #kg #mass\n", "u1=6 #m/s #Initial velocity\n", "\n", "#second body\n", "m2=30 #kg #mass\n", "u2=0 #m/s #Initial velocity\n", "\n", "#Calculation\n", "\n", "#MAss of two bodies\n", "M=m1+m2 #kg\n", "\n", "#Total momentum before impact\n", "M2=m1*u1+m2*u2 #kg*m/s\n", "\n", "#Total momentum after impact\n", "#M3=(m1+m2)*V #kg*m/s\n", "\n", "#Velocitites of two bodies\n", "V=M2*80**-1 #m/s\n", "\n", "#Result\n", "print\"Common Velocity is\",round(V,2),\"m/s\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Common Velocity is 3.75 m/s\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 17.3,Page No.651" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of Variables\n", "\n", "#Bullet\n", "m1=0.05 #Kg #mass\n", "\n", "#Target\n", "m2=5 #kg #mass\n", "u2=0 #m/s #Initital Velocity\n", "v=7 #m/s #Final Velocity\n", "\n", "#Calculation\n", "\n", "m=m1+m2 #kg #total mass\n", "\n", "#total Initial momentum\n", "#v1=m1*u1+m2*u2\n", "#After sub values and further simplifying we get\n", "#v1=0.05*u1\n", "\n", "#Total Final momentum\n", "v2=m*v #kg*m/s\n", "\n", "#Velocity of bullet\n", "u1=v2*0.05**-1 #m/s\n", "\n", "#Result\n", "print\"Velocity of bullet is\",round(u1,2),\"m/s\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Velocity of bullet is 707.0 m/s\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 17.4,Page No.651" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of Variables\n", "\n", "m1=20 #kg #MAss of first ball\n", "u1=5 #m/s #Initital velocity of first ball\n", "\n", "#second ball\n", "m2=10 #kg #mass \n", "u2=-10 #m/s #Velocity\n", "e=5*6**-1 #coefficient of restitution\n", "\n", "#Calculation\n", "\n", "#Total momentum before impact\n", "v1=m1*u1+m2*u2 #m/s\n", "\n", "\n", "#Total momentum after impact\n", "#v2=m1*v1+m2*v2\n", "\n", "#Velocity of second ball after impact\n", "V2=25*3**-1 #m/s \n", "\n", "#Velocity of first ball after impact\n", "V1=-V2*2**-1 #m/s\n", "\n", "#Result\n", "print\"Velocity of first ball after impact is\",round(V1,2),\"m/s\"\n", "print\"Velocity of second ball after impact is\",round(V2,2),\"m/s\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Velocity of first ball after impact is -4.17 m/s\n", "Velocity of second ball after impact is 8.33 m/s\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 17.6,Page No.654" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of Variables\n", "\n", "m1=1 #kg #mass of first ball\n", "m2=2 #kg #mass of second ball\n", "u1=6 #m/s #Initial velocity of first ball\n", "u2=2 #m/s #Initial velocity of second ball\n", "theta1=30 #degrees #angle made by first ball\n", "theta2=30 #degrees #angle made by second ball\n", "e=0.5 #coefficient of restitutiion\n", "\n", "#Calculation\n", "\n", "#for ball A\n", "#v1*sin(phi1)=3 .............1\n", "\n", "#for ball B\n", "#v2*sin(phi)=1 .............2\n", "\n", "#according to lwa of conservation of momentum\n", "#v1*cos(ph11)+2*v2*cos(phi2)=8.66 ..............3\n", "\n", "#coefficient of restitution for this case\n", "#v2*cos(ph12)-v1*cos(phi1)=1.732 .........4\n", "\n", "#Adding equation 3 and 4 we get\n", "#v2*cos(ph2)=3.464 ....................5\n", " \n", "#sub values in equation 3 we get\n", "#v1*cos(ph1)=1.732 .................6\n", "\n", "#dividing equation 1 by equation6\n", "phi1=arctan(3*1.732**-1)*(180*pi**-1)\n", "\n", "#dividing equation 2 by 5 we get\n", "phi2=arctan(1*3.464**-1)*(pi**-1*180)\n", "\n", "#sub value of phi2 in equation 5\n", "v2=3.464*(cos(phi2*pi*180**-1))**-1\n", "\n", "#sub value in equation 1\n", "v1=1.732*(cos(phi1*pi*180**-1))**-1\n", "\n", "#Result\n", "print\"velocity of 1Kg ball is\",round(v1,2),\"m/s\"\n", "print\"velocity of 2nd ball is\",round(v2,2),\"m/s\"\n", "print\"Direction of 1Kg ball is\",round(phi1,2),\"degrees\"\n", "print\"Direction of 2nd ball is\",round(phi2,2),\"Degrees\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "velocity of 1Kg ball is 3.46 m/s\n", "velocity of 2nd ball is 3.61 m/s\n", "Direction of 1Kg ball is 60.0 degrees\n", "Direction of 2nd ball is 16.1 Degrees\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 17.7,Page No.656" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of Variables\n", "\n", "m1=2 #kg #mass of first ball\n", "m2=2 #kg #mass of second ball\n", "u1=20 #m/s #Initial velocity of first ball\n", "u2=30 #m/s #Initial velocity of second ball\n", "theta1=30 #degrees #angle made by first ball\n", "theta2=60 #degrees #angle made by second ball\n", "e=0.9 #coefficient of restitutiion\n", "\n", "#Calculation\n", "\n", "#for ball A\n", "#v1*sin(phi1)=10 .............1\n", "\n", "#for ball B\n", "#v2*sin(phi)=25.98 .............2\n", "\n", "#according to lwa of conservation of momentum\n", "#v1*cos(ph11)+2*v2*cos(phi2)=2.32 ..............3\n", "\n", "#coefficient of restitution for this case\n", "#v2*cos(ph12)-v1*cos(phi1)=29.08 .........4\n", "\n", "#Adding equation 3 and 4 we get\n", "#v2*cos(ph2)=15.7 ....................5\n", " \n", "#sub values in equation 3 we get\n", "#v1*cos(ph1)=13.38 .................6\n", "\n", "#dividing equation 1 by equation6\n", "phi1=arctan(10*13.38**-1)*(180*pi**-1)\n", "\n", "#dividing equation 2 by 5 we get\n", "phi2=arctan(25.98*15.7**-1)*(pi**-1*180)\n", "\n", "#sub value of phi2 in equation 5\n", "v2=25.98*(sin(phi2*pi*180**-1))**-1\n", "\n", "#sub value in equation 1\n", "v1=13.38*(cos(phi1*pi*180**-1))**-1\n", "\n", "#Result\n", "print\"velocity of 1Kg ball is\",round(v1,2),\"m/s\"\n", "print\"velocity of 2nd ball is\",round(v2,2),\"m/s\"\n", "print\"Direction of 1Kg ball is\",round(phi1,2),\"degrees\"\n", "print\"Direction of 2nd ball is\",round(phi2,2),\"Degrees\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "velocity of 1Kg ball is 16.7 m/s\n", "velocity of 2nd ball is 30.36 m/s\n", "Direction of 1Kg ball is 36.77 degrees\n", "Direction of 2nd ball is 58.85 Degrees\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 17.8,Page No.658" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of Variables\n", "\n", "#First vechile\n", "m1=600 #kg #mass\n", "u1=12 #m/s #Initial velocity\n", "\n", "#Second vechile\n", "m2=400 #kg #mass\n", "u2=9 #m/s #initial velocity\n", "\n", "#Calculation\n", "\n", "#Total mass\n", "M=m1+m2 #kg\n", "\n", "#Total Momentum before impact\n", "v1=m1*u1+m2*u2\n", "\n", "#Total momentum\n", "#v=M*V\n", "\n", "#By law of conservation of momentum\n", "V=v1*1000**-1 #m/s\n", "\n", "#Kinetic Energy before impact\n", "KE1=(m1*u1**2+m2*u2**2)*2**-1 #N*m\n", "\n", "#Total KE after impact\n", "KE2=M*V**2*2**-1 #N*m\n", "\n", "#Loss of KE\n", "KE3=KE1-KE2 #N*m\n", "\n", "#Result\n", "print\"Loss of Kinetic Energy due to impact is\",round(KE3,2),\"N*m\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Loss of Kinetic Energy due to impact is 1080.0 N*m\n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 17.9,Page No.659" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of Variables\n", "\n", "m1=0.1 #kg #MAss of bullet\n", "m2=10 #kg #mass of target\n", "u2=0 #Initial velocity of target\n", "v=7 #m/s #common velocity\n", "\n", "#Calculation\n", "\n", "#Total momentum before impact\n", "#v1=0.1*u1\n", "\n", "#Total momentum after impact\n", "v2=(m1+m2)*v\n", "\n", "#Initial velocity of bullet\n", "u1=v2*0.1**-1 #m/s\n", "\n", "#Total KE before impact\n", "KE=(m1*u1**2+m2*u2**2)*2**-1\n", "\n", "#Total KE after impact\n", "KE2=(m1+m2)*v**2*2**-1 #m/s\n", "\n", "#Loss of KE\n", "KE3=KE-KE2 #N*m\n", "\n", "#Result\n", "print\"Loss of Kinetic Energy is\",round(KE3,2),\"N*m\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Loss of Kinetic Energy is 24745.0 N*m\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 17.12,Page No.662" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of Variables\n", "\n", "e=0.75 #coefficient of restitution\n", "m1=1 #kg #MAss of first sphere\n", "m2=5 #kg #mass of second sphere\n", "u1=3 #m/s #Initial velocity of 1st sphere\n", "u2=0.6 #m/s #Initial velocity of 2nd sphere\n", "\n", "#Calculation\n", "\n", "#From law of conservation of momentum equation we get\n", "#v1+5*v2=6 ..................1\n", "\n", "#Form coefficient of restitution formula we get\n", "#v2-v1=1.8 ........................2\n", "\n", "#Adding equations 1 and 2 we get\n", "v2=7.8*6**-1 #m/s\n", "\n", "#sub in equation 2 we get\n", "v1=1.8-v2 #m/s\n", "\n", "#Loss of KE during impact\n", "KE=((m1*u1**2+m2*u2**2)-(m1*v1**2+m2*v2**2))*2**-1\n", "\n", "#Result\n", "print\"Loss of Kinetic Energy during impact is\",round(KE,2),\"N*m\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Loss of Kinetic Energy during impact is 1.05 N*m\n" ] } ], "prompt_number": 9 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 17.13,Page No.664" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of Variables\n", "\n", "m=0.5 #kg #mass of ball\n", "H=18 #m #Height from which the ball is dropped\n", "h=8 # #Height to which ball rebounds\n", "g=9.81 #m/s**2 \n", "\n", "\n", "#Calculation\n", "\n", "#Velocity with which ball strikes the floor\n", "u=(2*g*H)**0.5 #m/s\n", "\n", "#Velocty of ball after impact\n", "v=(2*g*h)**0.5 #m/s\n", "\n", "#Coefficient of restitution\n", "e=v*u**-1\n", "\n", "#Result\n", "print\"coefficient of restitution between floor and ball\",round(e,2)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "coefficient of restitution between floor and ball 0.67\n" ] } ], "prompt_number": 10 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 17.13(A),Page No.664" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of Variables\n", "\n", "H1=1.6 #m #Initial Height\n", "H2=0.9 #m #Height after rebound\n", "g=9.81 #m/s**2\n", "\n", "#Calculation\n", "\n", "#Consider motion of ball from height H1, wwe get\n", "v1=(2*g*H1)**0.5 #m/s ................................1\n", "\n", "#Consider motion of ball from floor to a height H2\n", "u2=(2*g*H2)**0.5 #m/s .........................2\n", "\n", "#Dividing equation 2 by 1 we get\n", "e=u2*v1**-1 \n", "\n", "#Result\n", "print\"Coefficient of restitution is\",round(e,2)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Coefficient of restitution is 0.75\n" ] } ], "prompt_number": 11 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 17.14,Page No.665" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of Variables\n", "\n", "h=16 #m #Height after impact\n", "e=0.8 #coeficient of restitution\n", "g=9.81 #m/s**2\n", "\n", "#Calculation\n", "\n", "#Velocity with which ball strikes the floor\n", "u=(2*g*h)**0.5 #m/s \n", "\n", "#Height from which ball is dropped\n", "H=2*g*h*(e**2*2*g)**-1 #m\n", "\n", "#Result\n", "print\"Height from which the ball is dropped is\",round(H,2),\"m\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Height from which the ball is dropped is 25.0 m\n" ] } ], "prompt_number": 12 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 17.15,Page No.665" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of Variables\n", "\n", "H=13.5 #Height from which ball is dropped\n", "h=9 #m #Height to which ball rebounds\n", "g=9.81 #m/s**2\n", "\n", "#Calculation\n", "\n", "#velocity with which ball stirkes the floor\n", "u=(2*g*H)**0.5 #m/s\n", "\n", "#velocity of ball after impact\n", "v=(2*g*h)**0.5 #m/s\n", "\n", "#Coefficient of restitution \n", "e=(v*u**-1)\n", "\n", "#Height of second rebound\n", "\n", "#velocity with which ball stirkes the floor second time\n", "u1=(2*g*h) #m/s ..............1\n", "\n", "#velocity of ball after impact rebounds second time\n", "#v1=(2*g*h2) ....................2\n", " \n", "#After simplifying equation 1 and 2 we get\n", "h2=e**2*u1*(2*g)**-1 #m\n", "\n", "#Result\n", "print\"Height of second rebound is\",round(h2,2),\"m\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Height of second rebound is 6.0 m\n" ] } ], "prompt_number": 13 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 17.16,Page No.667" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of Variables\n", "\n", "u=10 #m/s #Initial velocity of ball\n", "alpha=30 #degrees #angle made by intial velocity\n", "theta=60 #degrees\n", "e=0.5 #coefficient of restitution\n", "\n", "#Calculation\n", "\n", "#As components of intial velocity and final velocity with line of impact is same at right angles\n", "#v*sin(phi)=8.66 ........1\n", "\n", "#v*cos(phi)=2.5 ................2\n", "\n", "#Dividing equation 1 by 2\n", "phi=arctan(8.66*2.5**-1)*(180*pi**-1)\n", "\n", "#Sub value in equation 1 we get\n", "v=8.66*(sin(phi*pi*180**-1))**-1 #m/s\n", "\n", "#Result\n", "print\"Direction of ball after impact is\",round(phi,2),\"Degrees\"\n", "print\"Velocity of ball after impact\",round(v,2),\"m/s\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Direction of ball after impact is 73.9 Degrees\n", "Velocity of ball after impact 9.01 m/s\n" ] } ], "prompt_number": 14 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 17.17,Page No.667" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of Variables\n", "\n", "u=5 #m/s #Initial velocity of body\n", "alpha=30 #Degrees #Angle made by initial velocity with fixed plane\n", "theta=60 #degrees\n", "phi=45 #degrees #angle made by final velocity\n", "beta=45 #degrees #Angle made by final velocity with line of impact\n", "\n", "#Calculation\n", "\n", "#Components of final velocity and initial velocity at right angles to line of impact\n", "v=u*sin(alpha*pi*180**-1)*(sin(phi*pi*180**-1))**-1 #m/s\n", "\n", "#For indirect impacton a fixed plane\n", "e=v*cos(phi*pi*180**-1)*(u*cos(theta*pi*180**-1))**-1\n", "\n", "#Result\n", "print\"coefficient of restitution between ball and fixed plane is\",round(e,2)\n", "print\"velocity of body after impact is\",round(v,2),\"m/s\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "coefficient of restitution between ball and fixed plane is 1.0\n", "velocity of body after impact is 3.54 m/s\n" ] } ], "prompt_number": 15 } ], "metadata": {} } ] }