{ "metadata": { "name": "", "signature": "sha256:be338ef971644a9f5f4678fb763a92b7fd97bf3ce5a24c5818759072b8dab2d8" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "1: Elasticity" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 1.1, Page number 30" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "L=3; #length of wire(m)\n", "A=6.25*10**-5; #cross sectional area(m**2)\n", "delta_L=3*10**-3; #increase in length(m)\n", "F=1.2*10**3; #force(N)\n", "\n", "#Calculation\n", "Y=F*L/(A*delta_L); #young's modulus(N/m**2)\n", "\n", "#Result\n", "print \"young's modulus is \",Y/10**10,\"*10**10 N/m**2\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "young's modulus is 1.92 *10**10 N/m**2\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 1.2, Page number 30" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "Y=2*10**11; #young's modulus(N/m**2)\n", "L=2.75; #length of wire(m)\n", "d=1*10**-3; #diameter(m)\n", "M=1; #applied load(kg)\n", "g=9.8; #acceleration due to gravity(N)\n", "\n", "#Calculation\n", "T=M*g; #tension(N)\n", "delta_L=T*L/(math.pi*(d/2)**2*Y); #increase in length of wire(m)\n", "\n", "#Result\n", "print \"increase in length of wire is\",round(delta_L*10**4,5),\"*10**-4 m\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "increase in length of wire is 1.71569 *10**-4 m\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 1.3, Page number 31" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "F=0.3; #force(N)\n", "d=5*10**-3; #displacement(m)\n", "L=6*10**-2; #length of solid(m)\n", "B=6*10**-2; #breadth of solid(m)\n", "h=2*10**-2; #height of solid(m)\n", "\n", "#Calculation\n", "s=F/(L*B); #shear stress(N/m**2)\n", "theta=d/h; #shear strain\n", "rm=s/theta; #rigidity modulus(N/m**2)\n", "\n", "#Result\n", "print \"shear stress is\",round(s,2),\"N/m**2\"\n", "print \"shear strain is\",theta\n", "print \"rigidity modulus is\",round(rm,2),\"N/m**2\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "shear stress is 83.33 N/m**2\n", "shear strain is 0.25\n", "rigidity modulus is 333.33 N/m**2\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 1.4, Page number 32" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "n=2.5*10**10; #rigidity modulus(N/m**2)\n", "L=30*10**-2; #thickness(m)\n", "A=12*10**-4; #surface area(m**2)\n", "delta_L=1.5*10**-2; #displacement(m)\n", "\n", "#Calculation\n", "F=n*A*delta_L/L; #shearing force(N)\n", "\n", "#Result\n", "print \"shearing force is\",F/10**6,\"*10**6 N\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "shearing force is 1.5 *10**6 N\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 1.6, Page number 33" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "Y=7.25*10**10; #young's modulus of silver(N/m**2)\n", "K=11*10**10; #bulk modulus of silver(N/m**2)\n", "\n", "#Calculation\n", "sigma=(3*K-Y)/(6*K); #poisson's ratio\n", "\n", "#Result\n", "print \"poisson's ratio is\",round(sigma,2)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "poisson's ratio is 0.39\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 1.7, Page number 34" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "L=3; #length of Cu wire(m)\n", "Y=12.5*10**10; #young's modulus(N/m**2)\n", "r=5*10**-4; #radius of wire(m)\n", "sigma=0.26; #poisson's ratio\n", "m=10; #load(kg)\n", "g=9.8; #acceleration due to gravity(N)\n", "\n", "#Calculation\n", "delta_L=m*g*L/(math.pi*r**2*Y); #extension produced(m)\n", "ls=sigma*delta_L/3; #lateral strain\n", "dd=ls*r*2; #decrease in diameter(m) \n", "\n", "#Result\n", "print \"extension produced is\",round(delta_L*10**3,2),\"*10**-3 m\"\n", "print \"lateral compression produced is\",round(dd*10**7,3),\"*10**-7 m\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "extension produced is 2.99 *10**-3 m\n", "lateral compression produced is 2.595 *10**-7 m\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 1.8, Page number 35" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "L=1; #length of wire(m)\n", "d=1*10**-3; #diameter of wire(m)\n", "n=2.8*10**10; #rigidity modulus of wire(N/m**2)\n", "theta=math.pi/2; #angle of twisting(radian)\n", "\n", "#Calculation\n", "C=math.pi**2*n*(d/2)**4/(4*L); #couple to be applied(Nm)\n", "\n", "#Result\n", "print \"couple to be applied is\",round(C*10**3,5),\"*10**-3 Nm\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "couple to be applied is 4.31795 *10**-3 Nm\n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 1.9, Page number 35" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "d=0.82*10**-3; #diameter of wire(m)\n", "delta_L=1*10**-3; #length of elongation produced(m)\n", "m=0.33; #load(kg)\n", "g=9.8; #acceleration due to gravity(N)\n", "n=2.2529*10**9; #rigidity modulus of wire(N/m**2)\n", "\n", "#Calculation\n", "Y=m*g/(math.pi*(d/2)**2*delta_L); #young's modulus(N/m**2)\n", "sigma=(Y/(2*n))-1; #poisson's ratio\n", "\n", "#Result\n", "print \"poisson's ratio is\",round(sigma,3)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "poisson's ratio is 0.359\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 1.10, Page number 36" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "p1=1.01*10**5; #atmospheric pressure(N/m**2)\n", "K=16*10**10; #bulk modulus(N/m**2)\n", "p2=10**2; #increased pressure(N/m**2)\n", "\n", "#Calculation\n", "dP=p1-p2; #change in pressure(N/m**2)\n", "dV=dP/K; #fractional change of volume\n", "\n", "#Result\n", "print \"change in volume of steel bar is\",round(dV*10**7,1),\"*10**-7 V m**3\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "change in volume of steel bar is 6.3 *10**-7 V m**3\n" ] } ], "prompt_number": 9 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 1.11, Page number 37" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "Y=1.013*10**10; #young's modulus of bar(N/m**2)\n", "b=2*10**-2; #breadth of bar(m)\n", "l=1; #length of bar(m)\n", "d=1*10**-2; #depth of bar(m)\n", "m=2; #load(kg)\n", "g=9.8; #acceleration due to gravity(N)\n", "\n", "#Calculation\n", "y=m*g*l**3/(4*Y*b*d**3); #depression produced in bar(m)\n", "\n", "#Result\n", "print \"depression produced in bar is\",round(y,6),\"m\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "depression produced in bar is 0.024186 m\n" ] } ], "prompt_number": 10 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 1.12, Page number 37" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "r=1.2*10**-2; #radius of cantilever(m)\n", "l=1.5; #length of cantilever(m)\n", "Y=19.5*10**10; #young's modulus(N/m**2)\n", "m=2; #load(kg)\n", "g=9.8; #acceleration due to gravity(N)\n", "\n", "#Calculation\n", "y=4*m*g*l**3/(3*Y*math.pi*(r**4)); #depression produced in cantilever(m)\n", "\n", "#Result\n", "print \"depression produced in cantilever is\",round(y*10**3,3),\"*10**-3 m\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "depression produced in cantilever is 6.943 *10**-3 m\n" ] } ], "prompt_number": 11 } ], "metadata": {} } ] }