{ "metadata": { "name": "", "signature": "sha256:1d76b1008117b9259d7e6a17a81353d60bd8490c5f9100521ab22a813e31d7f5" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter1-What Is Mechanical Design" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Ex2-pg13" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "print('MACHINE DESIGN \\n Timothy H. Wentzell, P.E. \\n EXAMPLE-1.2 Page 13 ') \n", "##Example 1.2\n", "\n", "Sy=61000. ##[psi] Tensile strength of AISI 1020 cold drawn steel from Appendix 4 Page no 470\n", "SF=2.; ##[] safety factor\n", "F=300.; ##[lb] Weight of the ball\n", "L=36.; ##[in] Length of round bar\n", "Sy=61000.; ##[psi] Tensile strength from Appendix 4\n", "M=F*L; ##[in*lb] Bending moment Appendix 2\n", "\n", "Sall=Sy/SF; ##[psi] Allowable stress \n", "Z=M/Sall; ##[in^3] Section modulus for bending Sall=M/Z\n", "D=(32.*Z/math.pi)**(1./3.); ##[in] Diameter of bar\n", "\n", "##Use 13/8 in bar\n", "D1=1.625;\n", "\n", "print'%s %.2f %s '%('\\n\\n Diameter of Bar is ',D1,' in');\n", "\n", "##Checking Deflection\n", "I=math.pi*D1**4/64.; ##[in^4] Moment of inertia Appendix 3\n", "E=30.*10**6.; ##[lb/in^2] Modulus of elasticity\n", "Delta=F*L**3./(3.*E*I); ##[in] Deflection \n", "\n", "##Note- In the book I=0.342 in^4 is used instead of I=0.3422814 in^4\n", "\n", "print'%s %.2f %s '%('\\n The deflection of bar is',Delta,' in');\n", "\n", "\n", "##Note: The deviation of answer from the answer given in the book is due to round off error.(In the book values are rounded while in scilab actual values are taken)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "MACHINE DESIGN \n", " Timothy H. Wentzell, P.E. \n", " EXAMPLE-1.2 Page 13 \n", "\n", "\n", " Diameter of Bar is 1.62 in \n", "\n", " The deflection of bar is 0.45 in \n" ] } ], "prompt_number": 1 } ], "metadata": {} } ] }