{ "metadata": { "name": "", "signature": "sha256:2c442a1cbc28b933d555165b6cb09fa7f45de31e28c837593e3048f115cafdbb" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 2 : Equilibrium of Floating Bodies" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 2.1 Page No : 26" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#initialisation of variables\n", "d= 40. \t#lb/ft**2 density of wood\n", "w= 4 \t#ft wide\n", "h= 6 \t#ft deep\n", "l= 12 \t#ft long \n", "\n", "#CALCULATIONS\n", "W= w*h*d*l\n", "V= W/64\n", "D= V/(w*l)\n", "\n", "#RESULTS\n", "print 'Volume of water print laced = %.f ft**3'%(V)\n", "print ' Depth of immersion = %.2f ft'%(D)\n", "print ' Centre of buoyancy = %.2f ft from base'%(D)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Volume of water print laced = 180 ft**3\n", " Depth of immersion = 3.75 ft\n", " Centre of buoyancy = 3.75 ft from base\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 2.3 Page No : 28" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from sympy import Symbol,solve\n", "import math \n", "\n", "#initialisation of variables\n", "d= 4. \t#ft diameter\n", "h= 7. \t#ft high\n", "W= 2500. \t#lb weighing \n", "OG= 3.5\n", "OB= 1.55 \t#ft\n", "\n", "#CALCULATIONS\n", "V= W/d**3\n", "D= V/(math.pi*(d/2)**2)\n", "I= math.pi*d**4/64\n", "BM= I/V\n", "BG= OG-OB\n", "T = Symbol(\"T\")\n", "ans = solve( (2500 + T)**2 -(512*math.pi *(8750 - 804)) - 1)\n", "T = ans[1]\n", "\n", "#RESULTS\n", "print 'Minimum tension in chain = %d lb'%(T)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Minimum tension in chain = 1075 lb\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 2.4 Page No : 31" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "import math \n", "\n", "#initialisation of variables\n", "W1= 1000. \t#lb weighing\n", "W2= 100. \t#lb load\n", "h= 4. \t#ft height\n", "d= 5. \t#ft diameter\n", "\n", "#CALCULATIONS\n", "V= (W1+W2)/h**3\n", "D= V*h/(d**2*math.pi)\n", "I= d**4*math.pi/h**3\n", "BM= I/V\n", "x= (BM+(D/2)-(W1*(h/2)/(W1+W2)))/(W2/(W1+W2))-0.02\n", "C= x-h\n", "\n", "#RESULTS\n", "print 'centre of gravity = %.2f ft'%(x)\n", "print ' Hence the gravity of the weight must not be more than above the top of buoy = %.2f ft'%(C)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "centre of gravity = 4.43 ft\n", " Hence the gravity of the weight must not be more than above the top of buoy = 0.43 ft\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 2.5 Page No : 32" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "\n", "#initialisation of variables\n", "b= 12. \t#ft breadth\n", "h1= 3. \t#ft draught\n", "h2= 1.5 \t#ft\n", "h3= 5+(2./3) \t#ft\n", "\n", "#CALCULATIONS\n", "I= b**3/12\n", "V= b*h1\n", "bm= I/V\n", "BG= bm+(h1*2/(3*b))\n", "O= math.degrees(math.tan(math.sqrt((h3*2-h1-bm*2)/(bm*2+bm))))\n", "\n", "\n", "#RESULTS\n", "print ' Volume of body immersed = %.f ft**3'%(V)\n", "print ' BM = %.f ft'%(bm)\n", "print ' BG = %.2f ft'%(BG)\n", "print ' angle of heel = %.2f degrees'%(O)\n", "\n", "#The answer is a bit different due to rounding off error in textbook\n", "\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " Volume of body immersed = 36 ft**3\n", " BM = 4 ft\n", " BG = 4.17 ft\n", " angle of heel = 9.64 degrees\n" ] } ], "prompt_number": 5 }, { "cell_type": "code", "collapsed": false, "input": [], "language": "python", "metadata": {}, "outputs": [] } ], "metadata": {} } ] }