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diff --git a/sample_notebooks/SachinNaik/ch8.ipynb b/sample_notebooks/SachinNaik/ch8.ipynb new file mode 100644 index 00000000..4459e9a8 --- /dev/null +++ b/sample_notebooks/SachinNaik/ch8.ipynb @@ -0,0 +1,356 @@ +{ + "metadata": { + "name": "" + }, + "nbformat": 3, + "nbformat_minor": 0, + "worksheets": [ + { + "cells": [ + { + "cell_type": "heading", + "level": 1, + "metadata": {}, + "source": [ + "Chapter 8: Brakes and Dynamometers" + ] + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 1, Page 252" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "\n", + "#Variable declaration\n", + "dia=12#in\n", + "r=dia/2\n", + "CQ=7#in\n", + "OC=6#in\n", + "OH=15#in\n", + "u=0.3\n", + "P=100#lb\n", + "\n", + "#Calculations\n", + "phi=math.atan(u)\n", + "x=r*math.sin(phi)#in inches;radius of friction circle\n", + "a=5.82#from figure\n", + "Tb=P*OH*x/a#braking torque\n", + "\n", + "#Result\n", + "print \"The braking torque of the drum Tb= %.f lb\"%Tb" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "The braking torque of the drum Tb= 444 lb\n" + ] + } + ], + "prompt_number": 1 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 2, Page 252" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "\n", + "#Variable declaration\n", + "OH=15#in\n", + "l=OH\n", + "u=0.3\n", + "P=100#lb\n", + "dia=12#in\n", + "r=dia/2\n", + "\n", + "#Calculations\n", + "phi=math.atan(u)\n", + "#according to fig 170(b)\n", + "#for clockwise rotation\n", + "a=6#from figure\n", + "x=r*math.sin(phi)#in inches;radius of friction circle\n", + "Tb=P*l*x/a#braking torque on the drum\n", + "#for counter clockwise rotation\n", + "a1=5.5#in\n", + "Tb1=P*l*x/a1#braking torque on the drum\n", + "#according to figure 172(a)\n", + "#for clockwise rotation\n", + "a2=6.48#from figure\n", + "x=r*math.sin(phi)#in inches;radius of friction circle\n", + "Tb2=P*l*x/a2#braking torque on the drum\n", + "#for counter clockwise rotation\n", + "a3=6.38#in\n", + "Tb3=P*l*x/a3#braking torque on the drum\n", + "T1=math.ceil(Tb1)\n", + "T2=math.ceil(Tb2)\n", + "T3=math.ceil(Tb3)\n", + "\n", + "#Result\n", + "print \"Braking torque on drum:\\nWhen dimensions are measured from fig 170(b)\\nFor clockwise rotation= %.f lb in\"\\\n", + "\"\\nFor counter clockwise rotation= %.f lb in\"%(Tb,T1)\n", + "print \"\\nWhen dimensions are measured from fig 171(a)\\nFor clockwise rotation= %.f lb in\"\\\n", + "\"\\nFor counter clockwise rotation= %.f lb\"%(T2,T3)\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Braking torque on drum:\n", + "When dimensions are measured from fig 170(b)\n", + "For clockwise rotation= 431 lb in\n", + "For counter clockwise rotation= 471 lb in\n", + "\n", + "When dimensions are measured from fig 171(a)\n", + "For clockwise rotation= 400 lb in\n", + "For counter clockwise rotation= 406 lb\n" + ] + } + ], + "prompt_number": 5 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 3, Page 253" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "\n", + "#Variable declaration\n", + "u=.35\n", + "Tb=500#lb.ft\n", + "rd=10#in\n", + "\n", + "#Calculations\n", + "phi=math.atan(u)\n", + "x=rd*math.sin(phi)\n", + "#F*OD=R*a=R1*a\n", + "#R=R1\n", + "#2*R*x=Tb\n", + "OD=24#in\n", + "a=11.5#inches; From figure\n", + "F=Tb*a*12/(OD*2*x)\n", + "#from figure\n", + "HG=4#in\n", + "GK=12#in\n", + "HL=12.22#in\n", + "P=F*HG/GK\n", + "Fhd=HL*P/HG\n", + "\n", + "#Results\n", + "print \"a) Magnitude of P = %.f lb\"%P\n", + "print \"b) Magnitude of Fhd = %.f lb\"%Fhd" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "a) Magnitude of P = 145 lb\n", + "b) Magnitude of Fhd = 443 lb\n" + ] + } + ], + "prompt_number": 6 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4, Page 259" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "\n", + "#Variable declaration\n", + "u=.3\n", + "theta=270*math.pi/180\n", + "l=18#in\n", + "a=4#in\n", + "Di=15#in\n", + "Do=21#in\n", + "w=.5#tons\n", + "\n", + "#Calculations\n", + "W=w*2204#lb\n", + "Q=W*Di/Do#required tangential braking force on the drum\n", + "k=math.e**(u*theta)#k=T1/T2\n", + "p=Q*a/(l*(k-1))\n", + "\n", + "#Result\n", + "print \"Least force required, P = %.f lb\"%p" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Least force required, P = 56 lb\n" + ] + } + ], + "prompt_number": 7 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 5, Page 264" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "\n", + "#Variable declaration\n", + "n=12\n", + "u=.28\n", + "a=4.5#in\n", + "b=1#in\n", + "l=21#in\n", + "r=15#in\n", + "Tb=4000#lb\n", + "\n", + "#Calculations\n", + "theta=10*math.pi/180\n", + "#k=Tn/To\n", + "k=((1+u*math.tan(theta))/(1-u*math.tan(theta)))**n\n", + "Q=Tb*(12./r)\n", + "P=Q*(a-b*k)/(l*(k-1))#from combining 8.6 with k=e^u*theta\n", + "\n", + "#Result\n", + "print \"The least effort required = P = %.1f lb\"%P" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "The least effort required = P = 82.2 lb\n" + ] + } + ], + "prompt_number": 8 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 6, Page 274" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#Variable declaration\n", + "w=9.5 #ft\n", + "h= 2. #ft\n", + "x=4. #ft\n", + "v=30.#mph\n", + "\n", + "#Calculations\n", + "V=1.46667*v#ft/s\n", + "u1=.1\n", + "u2=.6\n", + "g=32.2#ft/s**2\n", + "#a) rear wheels braked\n", + "fa1=(u1*(w-x)*g)/(w+u1*h)\n", + "fa2=(u2*(w-x)*g)/(w+u2*h)\n", + "sa1=V**2/(2*fa1)\n", + "sa2=V**2/(2*fa2)\n", + "#b) front wheels braked\n", + "fb1=u1*x*g/(w-u1*h)\n", + "fb2=u2*x*g/(w-u2*h)\n", + "sb1=V**2/(2*fb1)\n", + "sb2=V**2/(2*fb2)\n", + "#c) All wheels braked\n", + "fc1=u1*g\n", + "fc2=u2*g\n", + "sc1=V**2/(2*fc1)\n", + "sc2=V**2/(2*fc2)\n", + "k1=(x+u1*h)/(w-x-u1*h)#Na/Nb\n", + "k2=(x+u2*h)/(w-x-u2*h)#Na/Nb\n", + "\n", + "#Results\n", + "print \"Coefficient of friction = 0.1\\na) Minimum distance in which car may be stopped when the rear brakes are\"\\\n", + "\"applied = %.f ft\\nb) Minimum distance in which car may be stopped when the front brakes are applied = %.f ft\"\\\n", + "\"\\nc) Minimum distance in which car may be stopped when all brakes are applied = %.f ft\"%(sa1,sb1,sc1)\n", + "print \"\\nCoefficient of friction = 0.6\\na) Minimum distance in which car may be stopped when the rear brakes are \"\\\n", + "\"applied = %.1f ft\\nb) Minimum distance in which car may be stopped when the front brakes are applied = %.f ft\"\\\n", + "\"\\nc) Minimum distance in which car may be stopped when all brakes are applied = %.1f ft\"%(sa2,sb2,sc2)\n", + "print \"\\nRequired ration of Na/Nb\\nFor u1 = 0.1 -> %.3f\\nFor u2 = 0.6 -> %.2f\"%(k1,k2)" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Coefficient of friction = 0.1\n", + "a) Minimum distance in which car may be stopped when the rear brakes areapplied = 530 ft\n", + "b) Minimum distance in which car may be stopped when the front brakes are applied = 699 ft\n", + "c) Minimum distance in which car may be stopped when all brakes are applied = 301 ft\n", + "\n", + "Coefficient of friction = 0.6\n", + "a) Minimum distance in which car may be stopped when the rear brakes are applied = 97.5 ft\n", + "b) Minimum distance in which car may be stopped when the front brakes are applied = 104 ft\n", + "c) Minimum distance in which car may be stopped when all brakes are applied = 50.1 ft\n", + "\n", + "Required ration of Na/Nb\n", + "For u1 = 0.1 -> 0.792\n", + "For u2 = 0.6 -> 1.21\n" + ] + } + ], + "prompt_number": 9 + } + ], + "metadata": {} + } + ] +}
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