{ "metadata": { "name": "chapter 1 som.ipynb" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 1:Centre Of Gravity\n" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem 1.1,Page No.8" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of Variables\n", "\n", "#Rectangle-1\n", "a_1=37.5 #cm**2 \n", "y_1=26.25 #cm \n", "\n", "#Rectangle-2\n", "a_2=50 #cm**2 \n", "y_2=15 #cm \n", "\n", "#Rectangle-3\n", "a_3=150 #cm**2 \n", "y_3=2.5 #cm \n", "\n", "\n", "#Calculation\n", "\n", "\n", "Y_bar=(a_1*y_1+a_2*y_2+a_3*y_3)*(a_1+a_2+a_3)**-1 #cm \n", "\n", "#Result\n", "print\"The centroid of the section is\",round(Y_bar,2),\"cm\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The centroid of the section is 8.88 cm\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem 1.2,Page No.9" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of variables\n", "\n", "#Area-1\n", "a_1=6 #cm**2 \n", "x_1=3 #cm\n", "y_1=0.5 #cm\n", "\n", "#Area-2\n", "a_2=6 #cm**2\n", "x_2=2.671 #cm\n", "y_2=3 #cm\n", "\n", "#Area-3\n", "a_3=16 #cm**2\n", "x_3=1 #cm\n", "y_3=5 #cm\n", "\n", "\n", "#Calculation\n", "\n", "\n", "X_bar=(a_1*x_1+a_2*x_2+a_3*x_3)*(a_1+a_2+a_3)**-1 #cm\n", "Y_bar=(a_1*y_1+a_2*y_2+a_3*y_3)*(a_1+a_2+a_3)**-1 #cm\n", "\n", "\n", "#Result\n", "print\"The centre of gravity of section is\",round(X_bar,2),\"cm\"\n", "print\"The centre of gravity of section is\",round(Y_bar,2),\"cm\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The centre of gravity of section is 1.79 cm\n", "The centre of gravity of section is 3.61 cm\n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem 1.3,Page no.10" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of variables\n", "\n", "#Area-1\n", "a_1=93.75 #cm**2 \n", "y_1=6.25 #cm\n", "\n", "#Area-2\n", "a_2=93.75 #cm**2 \n", "y_2=6.25 #cm\n", "\n", "#Area-3\n", "a_3=375 #cm**2 \n", "y_3=9.375 #cm\n", "\n", "#Area-4\n", "a_4=353.43 #cm**2\n", "y_4=6.366 #cm\n", "\n", "\n", "#Calculation\n", "\n", "Y_bar=(a_1*y_1+a_2*y_2+a_3*y_3-a_4*y_4)*(a_1+a_2+a_3-a_4)**-1 #cm\n", "\n", "\n", "#Result\n", "print\"The centre of gravity lies at a distance of \",round(Y_bar,2),\"cm\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The centre of gravity lies at a distance of 11.66 cm\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem 1.4,Page no.10\n", "\n" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of variables\n", "\n", "\n", "a_1=36*pi #cm**2 #Area of Quadrant of a circle\n", "x_1=16/pi #cm \n", "y_1=16*pi**-1 #cm\n", "\n", "\n", "a_2=18*pi #cm**2 #Area of the semicircle\n", "x_2=6 #cm\n", "y_2=8*pi**-1 #cm\n", "\n", "\n", "#Calculation-1\n", "\n", "X_bar=(a_1*x_1-a_2*x_2)*(a_1-a_2)**-1 #cm\n", "\n", "#Calculation-2\n", "#To calculate Y_bar,taking AB as the Reference line\n", "\n", "Y_bar=(a_1*y_1-a_2*y_2)*(a_1-a_2)**-1 #cm\n", "\n", "#Result\n", "\n", "print\"The centre of gravity is \",round(X_bar,2),\"cm\"\n", "print\"The centre of gravity is\",round(Y_bar,2),\"cm\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The centre of gravity is 4.19 cm\n", "The centre of gravity is 7.64 cm\n" ] } ], "prompt_number": 9 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem 1.5,Page no.11" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of variables\n", "\n", "#Circle-1 \n", "a_1=100*pi #cm**2\n", "x_1=10 #cm\n", " \n", "#Square-2 \n", "a_2=50 #cm**2\n", "x_2=15 #cm\n", " \n", "#Calculation\n", "\n", "X_bar=(a_1*x_1-a_2*x_2)*(a_1-a_2)**-1 #cm\n", "\n", "\n", "#Result\n", "print\"The centre of gravity is\",round(X_bar,2),\"cm\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The centre of gravity is 9.05 cm\n" ] } ], "prompt_number": 10 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem 1.6,Page no.12\n" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#intilization of variables \n", "\n", "#Rectangle-1\n", "a_1=51200 #mm**2 \n", "x_1=160 #mm\n", "y_1=80 #mm\n", "\n", "#Triangle-2\n", "a_2=6400 #mm**2\n", "x_2=80*3**-1 #mm\n", "y_2=320*3**-1 #mm\n", "\n", "#Semicircle-3\n", "a_3=1250*pi #mm**2\n", "x_3=210 #mm\n", "y_3=(160-(4*50-(3*pi)**-1)) #mm\n", "\n", "\n", "#Calculation\n", "\n", "X_bar=(a_1*x_1-a_2*x_2-a_3*x_3)*(a_1-a_2-a_3)**-1 #mm\n", "Y_bar=(a_1*y_1-a_2*y_2-a_3*y_3)*(a_1-a_2-a_3)**-1 #mm\n", "\n", "#Result\n", "print\"The centroid of the given area is\",round(X_bar,2),\"mm\"\n", "print\"The centroid of the given area is\",round(Y_bar,2),\"mm\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The centroid of the given area is 176.07 mm\n", "The centroid of the given area is 87.34 mm\n" ] } ], "prompt_number": 27 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem 1.8,Page no.12" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of variables\n", "\n", "\n", "alpha=pi/2 #degree #In case of semicircle\n", "\n", "#Semicircle-1\n", "r_1=20 #cm #radius of semicircle \n", "y_1=4*r_1*(3*pi)**-1 #cm #distance from the base\n", "a_1=(pi*r_1**2)*2**-1 #cm**2 #area of semicircle\n", "\n", "#Semicircle-2\n", "r_2=16 #cm #radius of semicircle\n", "y_2=4*r_2*(3*pi)**-1 #cm #distance from the base\n", "a_2=(pi*r_2**2)*2**-1 #cm**2 #area of semicircle\n", "\n", "#Calculations\n", "\n", "\n", "Y_bar=(a_1*y_1-a_2*y_2)*(a_1-a_2)**-1 #cm #centroid\n", "\n", "\n", "#Result\n", "print\"The centroid of the area is \",round(Y_bar,2),\"cm\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The centroid of the area is 11.51 cm\n" ] } ], "prompt_number": 11 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Problem no1.12,Page no.16" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#Initilization of variables\n", "\n", "#Right Circular Cyclinder\n", "#m_1=(16*pi*h*rho_1) #gm \n", "#y_1=4+h*2**-1 #cm\n", "\n", "#Hemisphere\n", "#m_2=256*pi*rho_1 #gm \n", "y_2=2.5 #cm \n", "\n", "Y_bar=4 #cm\n", "r=4 #cm\n", "\n", "#Calculation\n", "\n", "#Y_bar=(m_1*y_1+m_2*y_2)*(m_1+m_2)**-1 #cm #Centroid\n", "h=(402.114*25.132**-1)**0.5\n", "\n", "#Result\n", "print\"The value of h is\",round(h,2),\"cm\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The value of h is 4.0 cm\n" ] } ], "prompt_number": 2 } ], "metadata": {} } ] }