{ "metadata": { "name": "", "signature": "sha256:8cc345c457c220087f4fe714f9742278677b74848dfd86669cab1fb48d07fa0d" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter2-Angular Motion" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "EX1-pg13" ] }, { "cell_type": "code", "collapsed": false, "input": [ "##Solutions to Problems In applied mechanics\n", "##A N Gobby\n", "import math\n", "##equation of motion, Mass of moment of inertia, percentage \n", "##reduction in speed\n", "##initialisation of variables\n", "g=5.##ft\n", "w=300.##rev/min\n", "a=0.86##red/s^2\n", "h=2240.##ft/s\n", "q=4.##ft\n", "g1=32.1##ft/s\n", "k=3105000.##ft lbf\n", "##CALCULATIONS\n", "T=(w*(2.*math.pi/60.))/(a)##sec\n", "M=(q*h*(g**2))/(g1)##slug ft^3\n", "K=((1/2.)*M)*((w*2.*math.pi**2)/(60.))##ft lbf\n", "W=math.sqrt(k/(1./2.)/M)##rad/s\n", "P=((((w*2.*math.pi)/60.)-W)/((w*2.*math.pi)/60.))*100.##percent\n", "##RESULTS\n", "print'%s %.2f %s'%('The equation of motion= ',T,' sec')\n", "print'%s %.2f %s'%('Mass of moment of inertia of = ',K,' ft lbf')\n", "print'%s %.2f %s'%('the percentage reduction in speed= ',P,' percent')\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The equation of motion= 36.53 sec\n", "Mass of moment of inertia of = 344360.03 ft lbf\n", "the percentage reduction in speed= 5.04 percent\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex2-pg15" ] }, { "cell_type": "code", "collapsed": false, "input": [ "##Solutions to Problems In applied mechanics\n", "##A N Gobby\n", "import math\n", "##radius of gyration\n", "##initialisation of variables\n", "m=2.58065##slug ft^3\n", "w=2.144##in\n", "##CALCULATIONS\n", "R=math.sqrt(m/w)##ft\n", "##RESULTS\n", "print'%s %.2f %s'%('The radius of gyration= ',R,' ft')\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The radius of gyration= 1.10 ft\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex3-pg15" ] }, { "cell_type": "code", "collapsed": false, "input": [ "##Solutions to Problems In applied mechanics\n", "##A N Gobby\n", "##distance travelled along incline before coming to rest\n", "import math\n", "##initialisation of variables\n", "w1=10.##tonf\n", "r=36.##in\n", "w=1./4.##tonf\n", "g=14.##in\n", "t=30.##mile/h\n", "s=100.##in\n", "m=20.##lbf/tonf\n", "h=2240.##lbf\n", "q=44.##in\n", "g1=32.2##ft\n", "##CALCULATIONS\n", "K=(w1*h*(q**2))/(2.*g1)##ft lbf \n", "L=q/1.5##rad/s\n", "R=(2.*1./2.*(1./4.*h/g1)*(g/12.)**2)*L**2##ft lbf\n", "T=K+R##ft lbf\n", "M=m*w1##lbf\n", "G=w1*h*(1./s)##lbf\n", "S=K/(M+G)##ft\n", "##RESULTS\n", "print'%s %.2f %s'%('the distance travelled along incline before coming to rest= ',S,' ft')\n", "#answer is different due to round off error\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "the distance travelled along incline before coming to rest= 1588.19 ft\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex4-pg16" ] }, { "cell_type": "code", "collapsed": false, "input": [ "##Solutions to Problems In applied mechanics\n", "##A N Gobby\n", "import math\n", "##percentage fluctuation in speed\n", "##initialisation of variables\n", "g=32.2##ft\n", "p=275.##rev/min\n", "w=1/2.*p##ft\n", "d=15.##hp\n", "h=33000.##ft\n", "r=0.8##ft\n", "h1=2240.##ft\n", "m=p*(2*math.pi/60.)##rad/s\n", "##CALCULATIONS\n", "W=(d*h)/w##ft lbf\n", "E=r*W##ft lbf\n", "I=(1.*h1*(3.)**2)/(g)##slug ft^2\n", "Q=(E*100.)/(I*(m)**2*2.)##percent\n", "##RESULTS\n", "print'%s %.2f %s'%('the percentage fluctuation in speed= ',Q,' percent')\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "the percentage fluctuation in speed= 0.28 percent\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex5-pg17" ] }, { "cell_type": "code", "collapsed": false, "input": [ "##Solutions to Problems In applied mechanics\n", "##A N Gobby\n", "import math\n", "##weight of flywheel and the work done by frictional torque\n", "##initialisation of variables\n", "w=140.##rev\n", "r=8.##in\n", "g=12.##in\n", "t=30.##mile/h\n", "q=(1/4.)##tonf\n", "I=0.99##slug ft^3\n", "p=32.2##ft^2\n", "##CALCULATIONS\n", "W=(I*p)/(r/g)**2##lbf\n", "T=(I*(2*math.pi)**2)/(2.*(2.*math.pi)*w)##lbf ft\n", "##RESULTS\n", "print'%s %.2f %s'%('The weight of flywheel=',W,'lbf')\n", "print'%s %.2f %s'%('the work done by frictional torque in stopping flywheel= ',T,' lbf ft')\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The weight of flywheel= 71.73 lbf\n", "the work done by frictional torque in stopping flywheel= 0.02 lbf ft\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex6-pg18" ] }, { "cell_type": "code", "collapsed": false, "input": [ "##Solutions to Problems In applied mechanics\n", "##A N Gobby\n", "##mass moment of inertia, kinetic enrgy and shear blades\n", "import math\n", "##initialisation of variables\n", "w=2.##tonf\n", "t=250.##rev/min\n", "g=32.2##ft\n", "h=2240.##ft\n", "f=0.8##percent\n", "t1=60.##ft\n", "s=1*(2./3.)##min\n", "r=480.##ft\n", "w1=20.##ft\n", "##CALCULATIONS\n", "M=(w*h*(w**2))/g##slug ft^2\n", "A=(t*(w*math.pi/t1))/t1*s##rad/s^2\n", "I=M*A##lbf ft\n", "K=1/2.*(M)*(2.*math.pi/t1)**2*r*w1##ft lbf\n", "F=f*K/(3./12.)##lbf\n", "##RESULTS\n", "print'%s %.2f %s'%('the mass moment of inertia = ',I,' lbf ft')\n", "print'%s %.2f %s'%('the kinetic energy= ',K,' ft lbf')\n", "print'%s %.2f %s'%('the average force on the shear blades= ',F,' lbf')\n", "#answer is different due to round off error" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "the mass moment of inertia = 161.89 lbf ft\n", "the kinetic energy= 29294.13 ft lbf\n", "the average force on the shear blades= 93741.22 lbf\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex7-pg19" ] }, { "cell_type": "code", "collapsed": false, "input": [ "##Solutions to Problems In applied mechanics\n", "##A N Gobby\n", "import math\n", "##frictional torque retarding and tangential braking acting\n", "##initialisation of variables\n", "h=2240.##ft\n", "w=0.06##ft\n", "w1=4.##ft\n", "q=12.##ft\n", "g=5.##ft\n", "g1=32.2##ft\n", "d=100.##rev/min\n", "f=120.##sec\n", "##CALCULATIONS\n", "T=w*(w1*h)*(w1/q)##lbf ft\n", "I=((w1*h*(g)**2)/g1)*d*(2.*math.pi/60.)##slug ft^2/s or lbf ft s\n", "M=I/T##sec\n", "P=430.8##lbf ft\n", "R=(P/2.5)##lbf\n", "##RESULTS\n", "print'%s %.2f %s'%('the frictional torque retarding= ',M,' sec')\n", "print'%s %.2f %s'%('the tangential braking acting= ',R,' lbf')\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "the frictional torque retarding= 406.52 sec\n", "the tangential braking acting= 172.32 lbf\n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex8-pg20" ] }, { "cell_type": "code", "collapsed": false, "input": [ "##Solutions to Problems In applied mechanics\n", "##A N Gobby\n", "##tangential force\n", "import math\n", "##initialisation of variables\n", "I=179.2##lbf ft\n", "h=2240.##ft\n", "w=4.##ft\n", "w1=5.##ft\n", "r=120.##ft\n", "g=32.2##ft\n", "p=100.##ft\n", "t=60.##ft\n", "##CALCULATIONS\n", "M=(w*h*(w1)**2)/g##slug ft^3\n", "T=I/M##rad/s\n", "D=p*(2.*math.pi)/(t*T)##sec\n", "N=(p*(2.*math.pi)/t)/r##rad/s^2\n", "T1=M*N##lbf ft\n", "B=T1-I##lbf ft\n", "F=B/2.*1/2.##lbf\n", "##RESULTS\n", "print'%s %.2f %s'%('the deceleration = ',D,' sec')\n", "print'%s %.2f %s'%('the tangential force on brake rim= ',F,' lbf')\n", "#answer is different due to round off error" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "the deceleration = 406.52 sec\n", "the tangential force on brake rim= 106.97 lbf\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex9-pg20" ] }, { "cell_type": "code", "collapsed": false, "input": [ "##Solutions to Problems In applied mechanics\n", "##A N Gobby\n", "##friction of bearings is to to neglected\n", "import math\n", "##initialisation of variables\n", "h=2240.##ft\n", "g=32.2##ft\n", "g1=15.##in\n", "w=1200.##lbf\n", "q=12.##ft\n", "r=1.5##ft\n", "t=3.28##tonf ft\n", "t1=1.7##tonf ft\n", "x=550.##ft\n", "s=6.##ft\n", "##CALCULATIONS\n", "T=((w*(g1/q)**2)/(h*g))*(3./r)##tonf ft\n", "T1=t-t1+T##tonf ft\n", "W=(T1*h*s/(r))/(x)##ft lbf\n", "##RESULTS\n", "print'%s %.2f %s'%('the friction of bearings is to to neglected =',W,'')\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "the friction of bearings is to to neglected = 26.59 \n" ] } ], "prompt_number": 9 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex10-pg22" ] }, { "cell_type": "code", "collapsed": false, "input": [ "##Solutions to Problems In applied mechanics\n", "##A N Gobby\n", "import math\n", "##torque to acceleration drum and truck\n", "\n", "##initialisation of variables\n", "v=20.##ft/s\n", "s=150.##ft\n", "h=2240.##ft\n", "g=32.2##ft\n", "d=3.##ft\n", "p=364.9##lbf\n", "q=4##ft\n", "##CALCULATIONS\n", "A=v**2/(2.*s)##ft/s^2\n", "T=(h*(d)**2/g)*(A/q)+p*q##lbf ft\n", "##RESULTS\n", "print'%s %.2f %s'%('the torque to acceleration drum and truck= ',T,' lbf ft')\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "the torque to acceleration drum and truck= 1668.30 lbf ft\n" ] } ], "prompt_number": 10 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex11-pg22" ] }, { "cell_type": "code", "collapsed": false, "input": [ "##Solutions to Problems In applied mechanics\n", "##A N Gobby\n", "import math\n", "##gravitational force\n", "##initialisation of variables\n", "v=35.##hp\n", "p=25.##percent\n", "v1=30.##mile/h\n", "q=28.##in\n", "d=30.##in\n", "w=3200.##lbf\n", "t=33000.##lbf\n", "s=88.##in\n", "W=w*(1./v1)##lbf\n", "m=0.364##mile/h\n", "##CALCULATIONS\n", "N=(v1*s/60.)/(14./12.)*(60./(2*math.pi))##rev/min\n", "Ne=N*6.##rev/min\n", "E=(v*t)/(2.*math.pi*Ne)##lbf ft\n", "T=(v*0.75*t)/(2.*math.pi*N)##lbf ft\n", "P=T/(14./12.)##lbf\n", "V=math.sqrt((P-W)/m)##mile/h\n", "##RESULTS\n", "print'%s %.2f %s'%('the gravitational force= ',V,'mile/h')\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "the gravitational force= 24.67 mile/h\n" ] } ], "prompt_number": 11 } ], "metadata": {} } ] }