{ "metadata": { "name": "", "signature": "sha256:e231d69245822a18a4c67d44b8a7db0b930a7622a43a07f791250d8e1c3f4a37" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 3 : Hydrostatic Pressure" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.1 Page No : 29" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "# Variables :\n", "D = 30*10**-2;\t\t\t#in m\n", "F = 9810.;\t\t\t#in N\n", "\n", "# Calculations\n", "A = math.pi*D**2/4;\t\t\t#in m**2\n", "p = F/A;\t\t\t#in N/m**2 or Pa\n", "p = p/1000;\t\t\t#kPa\n", "\n", "# Results\n", "print \"Intensity of pressure at the bottom of container in kPa : %.2f\"%p\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Intensity of pressure at the bottom of container in kPa : 138.78\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.2 Page No : 29" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\t\t\t\n", "# Variables :\n", "h = 1.5;\t\t\t#in m\n", "w_w = 9.81;\t\t\t#in kN/m**3\n", "w_g = 1.26;\t\t\t#in kN/m**3\n", "w_m = 13.6;\t\t\t#in kN/m**3\n", "\n", "# Calculations and Results\n", "f = h*w_w;\t\t\t#kN/m**2\n", "print \"Intensity of pressure exerted by water column in kN/m**2 : \",f\n", "f = h*w_w*w_g;\t\t\t#kN/m**2\n", "print \"Intensity of pressure exerted by glycerine column in kN/m**2 : \",f\n", "f = h*w_w*w_m;\t\t\t#kN/m**2\n", "print \"Intensity of pressure exerted by mercury column in kN/m**2 : \",f\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Intensity of pressure exerted by water column in kN/m**2 : 14.715\n", "Intensity of pressure exerted by glycerine column in kN/m**2 : 18.5409\n", "Intensity of pressure exerted by mercury column in kN/m**2 : 200.124\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.3 Page No : 30" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\t\t\t\n", "# Variables :\n", "p = 2;\t\t\t#in kN/m**2\n", "w_w = 9.81;\t\t\t#in kN/m**3\n", "w_alcohol = w_w*0.789;\t\t\t#in kN/m**3\n", "w_m = 13.6;\t\t\t#in kN/m**3\n", "\n", "# Calculations and Results\n", "H = p/w_alcohol;\t\t\t#in m\n", "print \"Depth of alcohol in meter : %.3f\"%H\n", "P_head_w = p/w_w;\t\t\t#m\n", "print \"Pressure head in terms of water in meter : %.3f\"%P_head_w\n", "P_head_m = p/w_w/w_m;\t\t\t#m\n", "print \"Pressure head in terms of mercury in meter : %.3f\"%P_head_m\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Depth of alcohol in meter : 0.258\n", "Pressure head in terms of water in meter : 0.204\n", "Pressure head in terms of mercury in meter : 0.015\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.4 Page No : 31\n" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\t\t\t\n", "# Variables :\n", "Hwater = 6.;\t\t\t#m(Pressure head of water)\n", "S_oil = 0.70;\t\t\t#(specific gravity of oil)\n", "\n", "# Calculations and Results\n", "H_oil = Hwater/S_oil;\t\t\t#in m(Pressure head in terms of oil)\n", "print \"Pressure head of water in terms of oil in meter : %.2f\"%H_oil\n", "S_oil = 0.825;\t\t\t#(specific gravity of oil)\n", "S_mercury = 13.6;\t\t\t#(specific gravity of mercury)\n", "Hmercury = 70./100;\t\t\t#m(Pressure head of mercury)\n", "H_oil = S_mercury/S_oil*Hmercury;\t\t\t#in m(Pressure head in terms of oil)\n", "print \"Pressure head of mercury in terms of oil in meter : %.3f\"%H_oil\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Pressure head of water in terms of oil in meter : 8.57\n", "Pressure head of mercury in terms of oil in meter : 11.539\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.5 Page No : 36" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\t\t\t\n", "# Variables :\n", "w = 9.81;\t\t\t#in kN/m**3\n", "l = 3.;\t\t\t#in m\n", "b = 2.;\t\t\t#in m\n", "h = 1.;\t\t\t#in m\n", "\n", "# Calculations and Results\n", "f_bottom = w*h;\t\t\t#in kN/m**2(Pressure intensity at bottom)\n", "p_bottom = f_bottom*l*b;\t\t\t#kN\n", "print \"Total pressure on the bottom in kN : \",p_bottom\n", "f_long_vertical = f_bottom/2;\t\t\t#kN\n", "p_long_vertical = f_long_vertical*l*h;\t\t\t#kN\n", "print \"Total pressure on long vertical wall in kN : \",p_long_vertical\n", "f_short_vertical = f_bottom/2;\t\t\t#kN\n", "p_short_vertical = f_short_vertical*b*h;\t\t\t#kN\n", "print \"Total pressure on short vertical wall in kN : \",p_short_vertical\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Total pressure on the bottom in kN : 58.86\n", "Total pressure on long vertical wall in kN : 14.715\n", "Total pressure on short vertical wall in kN : 9.81\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.6 Page No : 37" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\t\t\t\n", "# Variables :\n", "p_water = 1000.;\t\t\t#in kg/m**3\n", "p_liquid = 800.;\t\t\t#in kg/m**3\n", "g = 9.81;\t\t\t#gravity consmath.tant\n", "h1 = 1.5;\t\t\t#m\n", "\n", "# Calculations and Results\n", "px1 = p_liquid*g*h1/1000;\t\t\t#kN/m**2\n", "print \"Pressure at a point 1.5 meter below free surface in kN/m**2 : \",px1\n", "h2 = 2.;\t\t\t#m\n", "px2 = p_liquid*g*h2/1000;\t\t\t#kN/m**2\n", "print \"Pressure at a point 2 meter below free surface in kN/m**2 : \",px2\n", "h31 = 2.;\t\t\t#m(for liquid)\n", "h32 = 0.5;\t\t\t#m(for water)\n", "px1 = p_liquid*g*h31/1000;\t\t\t#kN/m**2\n", "px2 = p_water*g*h32/1000;\t\t\t#kN/m**2\n", "px3 = (px1+px2);\t\t\t#kN/m**2\n", "print \"Pressure at a point 2.5 meter below free surface in kN/m**2 : \",px3\n", "h = 2.;\t\t\t#meter(water level)\n", "b = 8.;\t\t\t#meter(width of wall)\n", "p_bottom = px1+(p_water*g*h)/1000;\t\t\t#kN/m**2\n", "p_avg1 = (px1+0)/2;\t\t\t#kN/m**2(top 2m liquid layer)\n", "p_avg2 = (px1+p_bottom)/2;\t\t\t#kN/m**2(top 2m water layer)\n", "F_per_meter = p_avg1*h*1+p_avg2*h*1;\t\t\t#kN\n", "Fwall = F_per_meter*b;\t\t\t#kN\n", "print \"Force on the wall in kN : \",Fwall\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Pressure at a point 1.5 meter below free surface in kN/m**2 : 11.772\n", "Pressure at a point 2 meter below free surface in kN/m**2 : 15.696\n", "Pressure at a point 2.5 meter below free surface in kN/m**2 : 20.601\n", "Force on the wall in kN : 533.664\n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.7 Page No : 46" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\t\t\t\n", "# Variables :\n", "b = 3.;\t\t\t#in meter\n", "h = 3.;\t\t\t#in meter\n", "S_oil = 0.8;\t\t\t#(specific gravity of oil)\n", "\n", "# Calculations\n", "A = 1./2*h*b;\t\t\t#in m**2\n", "x_bar = 2./3*3;\t\t\t#in meter\n", "SW_water = 9.81*1000;\t\t\t#in N/m**3\n", "SW_oil = SW_water*S_oil;\t\t\t#in N/m**3\n", "F_surface = SW_oil*A*x_bar;\t\t\t#in kN\n", "IG = b*h**3/36;\t\t\t#in m**3\n", "h_bar = IG/A/x_bar+x_bar;\t\t\t#in meter\n", "\n", "# Results\n", "print \"Force shall act at depth of centre of pressure. This depth in meter is : \",h_bar\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Force shall act at depth of centre of pressure. This depth in meter is : 2.25\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.8 Page No : 47" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\t\t\t\n", "# Variables :\n", "l = 3.;\t\t\t#in meter\n", "b = 2.;\t\t\t#in meter\n", "p = 2.*10**6;\t\t\t#in Pa\n", "g = 9.81;\t\t\t#gravity consmath.tant\n", "w = g*1000.;\t\t\t#in N/m**3\n", "\n", "# Calculations and Results\n", "h = p/w;\t\t\t#in meter\n", "xbar = h-1.5;\t\t\t#in meter\n", "A = l*b;\t\t\t#in m**2\n", "p_gate = w*A*xbar/10**6;\t\t\t#in MN\n", "print \"Total pressure on the gate in MN : %.3f\"%p_gate\n", "IG = b*l**3/12;\t\t\t#in m**3\n", "h_bar = IG/A/xbar+xbar;\t\t\t#in meter\n", "print \"Position of centre of pressure is \",round(h_bar-xbar,3),\" meter below the centroid of gate.\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Total pressure on the gate in MN : 11.912\n", "Position of centre of pressure is 0.004 meter below the centroid of gate.\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.9 Page No : 48" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\t\t\t\n", "# Variables :\n", "g = 9.81;\t\t\t#gravity\n", "GH = 4.;\t\t\t#meter\n", "IJ = 4.;\t\t\t#meter\n", "IC = 2.;\t\t\t#meter\n", "GC = 3.;\t\t\t#meter\n", "AG = (10.-4)/2;\t\t\t#meter\n", "BH = (10.-4)/2;\t\t\t#meter\n", "EI = AG*IC/GC;\t\t\t#meter\n", "JF = AG*IC/GC;\t\t\t#meter\n", "EF = EI+IJ+JF;\t\t\t#meter\n", "A = (8.+4.)/2*2;\t\t\t#in m**2\n", "a = 4.;\t\t\t#meter\n", "b = 8.;\t\t\t#meter\n", "d = 2.;\t\t\t#meter\n", "\n", "# Calculations and Results\n", "xbar = (2*a+b)/(a+b)*d/3;\t\t\t#in meter\n", "w = g*1000;\t\t\t#in N/m**3\n", "p_gate = w*A*xbar/10**3;\t\t\t#in kN\n", "print \"Total pressure in kN : \",p_gate\n", "IG = (a**2+4*a*b+b**2)/(a+b)*d**3/36;\t\t\t#in m**3\n", "h_bar = IG/A/xbar+xbar;\t\t\t#in meter\n", "print \"Depth of centre of pressure is \",h_bar,\" meter.\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Total pressure in kN : 104.64\n", "Depth of centre of pressure is 1.25 meter.\n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.10 Page No : 50" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\t\t\t\n", "# Variables :\n", "g = 9.81;\t\t\t#gravity\n", "xbar = 8.;\t\t\t#meter\n", "D = 4.;\t\t\t#meter\n", "\n", "# Calculations and Results\n", "A = math.pi*D**2/4;\t\t\t#meter**2\n", "w = g*1000;\t\t\t#in N/m**3\n", "p = w*A*xbar/10**3;\t\t\t#in kN\n", "print \"Total pressure in kN : %.2f\"%p\n", "IG = math.pi*D**4/64;\t\t\t#in m**4\n", "h_bar = IG/A/xbar+xbar;\t\t\t#in meter\n", "print \"Depth of centre of pressure is \",(h_bar),\" meter.\"\n", "\n", "# note : Answer of total pressure is wrong in the book.\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Total pressure in kN : 986.21\n", "Depth of centre of pressure is 8.125 meter.\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.11 Page No : 51" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "\t\t\t\n", "# Variables :\n", "g = 9.81;\t\t\t#gravity\n", "D = 4.;\t\t\t#meter\n", "xbar = (10.+7)/2;\t\t\t#meter\n", "\n", "# Calculations and Results\n", "A = math.pi*D**2/4;\t\t\t#meter**2\n", "w = g*1000;\t\t\t#in N/m**3\n", "p = w*A*xbar/10**6;\t\t\t#in MN\n", "print \"Total pressure in MN : %.3f\"%p\n", "BC = 3;\t\t\t#meter\n", "AB = 4;\t\t\t#mete\n", "math.sin_theta = BC/AB;\n", "IG = math.pi*D**4/64;\t\t\t#in m**4\n", "h_bar = IG/A/xbar*math.sin_theta**2+xbar;\t\t\t#in meter\n", "print \"Position of centre of pressure is \",(h_bar),\" meter.\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Total pressure in MN : 1.048\n", "Position of centre of pressure is 8.5 meter.\n" ] } ], "prompt_number": 9 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.12 Page No : 52" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "\t\t\t\n", "# Variables :\n", "a = 3.;\t\t\t#meter\n", "b = 4.;\t\t\t#meter(altitude)\n", "S = 1.2;\t\t\t#specific gravity\n", "theta = 30.;\t\t\t#degree\n", "d = 2.5;\t\t\t#meter\n", "g = 9.81;\t\t\t#gravity\n", "AG = b/3;\t\t\t#meter\n", "\n", "# Calculations and Results\n", "xbar = d+AG*math.sin(math.radians(theta));\t\t\t#meter\n", "A = 1./2*a*b;\t\t\t#meter**2\n", "w = S*g*1000;\t\t\t#in N/m**3\n", "p = w*A*xbar/10**3;\t\t\t#in kN\n", "print \"Total pressure in kN : \",p\n", "IG = a*b**3/36;\t\t\t#in m**4\n", "h_bar = IG/A/xbar*(math.sin(math.radians(theta)))**2+xbar;\t\t\t#in meter\n", "print \"Depth of centre of pressure is \",round(h_bar,3),\" meter.\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Total pressure in kN : 223.668\n", "Depth of centre of pressure is 3.237 meter.\n" ] } ], "prompt_number": 10 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.13 Page No : 54" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "\n", "# Variables :\n", "a = 8.;\t\t\t#meter\n", "b = 6.;\t\t\t#meter\n", "h = 3.;\t\t\t#meter\n", "CD = 2.;\t\t\t#meter\n", "theta = 30.;\t\t\t#degree\n", "\n", "# Calculations and Results\n", "A = (a+b)/2*h;\t\t\t#meter**2\n", "AB = (a+2*b)/(a+b)*h/3;\t\t\t#meter\n", "x1bar = AB;\t\t\t#meter\n", "BC = AB*math.sin(math.radians(theta));\t\t\t#meter\n", "BD = BC+CD;\t\t\t#meter\n", "xbar = BD;\t\t\t#meter\n", "g = 9.81;\t\t\t#gravity\n", "w = g*1000;\t\t\t#in N/m**3\n", "p = w*A*xbar/10**3;\t\t\t#in kN\n", "print \"Total pressure in kN : \",p\n", "IG = (a**2+b**2+4*a*b)/(a+b)*h**3/36;\t\t\t#in m**4\n", "h_bar = IG/A/xbar*(math.sin(math.radians(theta)))**2+xbar;\t\t\t#in meter\n", "print \"Depth of centre of pressure is \",round(h_bar,3),\" meter.\"\n", "\n", "# note : rounding off error" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Total pressure in kN : 559.17\n", "Depth of centre of pressure is 2.783 meter.\n" ] } ], "prompt_number": 11 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.14 Page No : 55" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "\t\t\t\n", "# Variables :\n", "l = 2.;\t\t\t#meter\n", "b = 2.;\t\t\t#meter\n", "p_i = 98.1;\t\t\t#kN/m**3(Pressure intensity)\n", "w = 9.81;\t\t\t#kN/m**2\n", "BC = 1.;\t\t\t#meter\n", "AB = 2.;\t\t\t#meter\n", "theta = 30.;\t\t\t#degree\n", "B = p_i/w;\t\t\t#m\n", "\n", "# Calculations\n", "BD = BC*math.sin(math.radians(theta));\t\t\t#m\n", "xbar = 10+0.5;\t\t\t#meter\n", "A = l*b;\t\t\t#m**2\n", "p = w*A*xbar;\t\t\t#kN\n", "IG = (2*l**3)/12;\t\t\t#in m**4\n", "h_bar = IG/A/xbar*(math.sin(math.radians(theta)))**2+xbar;\t\t\t#in meter\n", "DI = h_bar-xbar;\t\t\t#m\n", "FC = DI/math.sin(math.radians(theta));\t\t\t#m\n", "FB = FC+BC;\t\t\t#meter\n", "P = p*FB/AB;\t\t\t#kN\n", "\n", "# Results\n", "print \"Force in kN : \",P\n", "RB = p-P;\t\t\t#kN\n", "print \"Reaction at hinge B in kN : \",RB\n", "\n", "#Answer in the book is slightly differ due to limited accuracy used in the book as compared to SCILAB.\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Force in kN : 209.28\n", "Reaction at hinge B in kN : 202.74\n" ] } ], "prompt_number": 12 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.15 Page No : 57" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "\t\t\t\n", "# Variables :\n", "l = 4.;\t\t\t#meter\n", "b = 2.;\t\t\t#meter\n", "h = 1.8;\t\t\t#meter\n", "w = 9.81;\t\t\t#kN/m**2\n", "xbar = 6.-2\t\t\t#meter\n", "\n", "# Calculations\n", "A = l*b;\t\t\t#m**2\n", "P = w*A*xbar;\t\t\t#kN\n", "IG = (2*l**3)/12;\t\t\t#in m**4\n", "h_bar = IG/A/xbar+xbar;\t\t\t#in meter\n", "# As P acts at h_bar-xbar : \n", "F = P*((h_bar-xbar)-(b-h))/h;\t\t\t#kN\n", "\n", "# Results\n", "print \"Horizontal Force in kN : %.3f\"%F\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Horizontal Force in kN : 23.253\n" ] } ], "prompt_number": 13 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.16 Page No : 58" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "\t\t\t\n", "# Variables :\n", "b = 2.;\t\t\t#meter\n", "d = 3.;\t\t\t#meter\n", "h = 2.;\t\t\t#meter\n", "w = 9.81;\t\t\t#kN/m**2\n", "xbar = 2+3./2;\t\t\t#meter\n", "\n", "# Calculations and Results\n", "A = b*d;\t\t\t#m**2\n", "P = w*A*xbar;\t\t\t#kN\n", "print \"Total Pressure in kN : \",P\n", "IG = (b*d**3)/12;\t\t\t#in m**4\n", "h_bar = IG/A/xbar+xbar;\t\t\t#in meter\n", "print \"Position of centre of pressure in meter : %.3f\"%h_bar\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Total Pressure in kN : 206.01\n", "Position of centre of pressure in meter : 3.714\n" ] } ], "prompt_number": 14 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.17 Page No : 59" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\t\t\t\n", "# Variables :\n", "b = 4.;\t\t\t#meter\n", "d = 4.;\t\t\t#meter\n", "h = 8.;\t\t\t#meter\n", "w = 9.81;\t\t\t#kN/m**2\n", "xbar = 8.;\t\t\t#meter\n", "\n", "# Calculations and Results\n", "A = b*d;\t\t\t#m**2\n", "P = w*A*xbar;\t\t\t#kN\n", "print \"Total Pressure in kN : \",P\n", "IG = (b*d**3)/12;\t\t\t#in m**4\n", "h_bar = IG/A/xbar+xbar;\t\t\t#in meter\n", "print \"Position of centre of pressure in meter : %.3f\"%h_bar\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Total Pressure in kN : 1255.68\n", "Position of centre of pressure in meter : 8.167\n" ] } ], "prompt_number": 15 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.18 Page No : 60" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "\t\t\t\n", "# Variables :\n", "D = 1.5;\t\t\t#meter\n", "BE = 2.;\t\t\t#meter\n", "AD = 0.75;\t\t\t#meter\n", "CE = AD;\t\t\t#meter\n", "\n", "# Calculations and Results\n", "BC = BE-AD;\t\t\t#meter\n", "FG = CE+BC/2;\t\t\t#meter\n", "xbar = FG;\t\t\t#meter\n", "w = 9.81;\t\t\t#kN/m**2\n", "A = math.pi*D**2/4;\t\t\t#m**2\n", "AB = D;\t\t\t#meter\n", "sin_theta = BC/AB;\n", "P = w*A*xbar;\t\t\t#kN\n", "print \"Total Pressure in kN : %.3f\"%P\n", "IG = (math.pi/64*D**4);\t\t\t#in m**4\n", "h_bar = IG/A/xbar*sin_theta**2+xbar;\t\t\t#in meter\n", "print \"Position of centre of pressure in meter : %.3f\"%h_bar\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Total Pressure in kN : 23.837\n", "Position of centre of pressure in meter : 1.446\n" ] } ], "prompt_number": 16 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.19 Page No : 62" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\t\t\t\n", "# Variables :\n", "b = 3.;\t\t\t#meter\n", "a = 3.;\t\t\t#meter\n", "S_oil = 0.8;\t\t\t#specific gravity of oil\n", "w = 9.81*S_oil;\t\t\t#kN/m**2\n", "xbar = 1./3*b;\t\t\t#meter\n", "A = 1./2*a*b;\t\t\t#m**2\n", "\n", "# Calculations and Results\n", "P = w*A*xbar;\t\t\t#kN\n", "print \"Total Pressure in kN : \",P\n", "IG = (a*b**3)/36;\t\t\t#in m**4\n", "h_bar = IG/A/xbar+xbar;\t\t\t#in meter\n", "print \"Centre of pressure in meter : \",h_bar\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Total Pressure in kN : 35.316\n", "Centre of pressure in meter : 1.5\n" ] } ], "prompt_number": 17 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.20 Page No : 63" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\t\t\t\n", "# Variables :\n", "a = 2.;\t\t\t#meter\n", "b = 1.;\t\t\t#meter\n", "d = 2.;\t\t\t#meter\n", "w = 9.81;\t\t\t#kN/m**2\n", "xbar = 2+a/2;\t\t\t#meter\n", "\n", "# Calculations and Results\n", "A = a*b;\t\t\t#m**2\n", "P = w*A*xbar;\t\t\t#kN\n", "print \"Total Pressure in kN : \",P\n", "IG = (b*d**3)/12;\t\t\t#in m**4\n", "h_bar = IG/A/xbar+xbar;\t\t\t#in meter\n", "print \"Position of centre of pressure in meter : %.3f\"%h_bar\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Total Pressure in kN : 58.86\n", "Position of centre of pressure in meter : 3.111\n" ] } ], "prompt_number": 18 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.21 Page No : 67" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "\n", "# Variables :\n", "r = 2.;\t\t\t#meter\n", "l = 4.;\t\t\t#meter\n", "A = r*l;\t\t\t#m**2\n", "xbar = 2+r/2;\t\t\t#meter\n", "w = 9.81;\t\t\t#kN/m**2\n", "\n", "# Calculations and Results\n", "PH = w*A*xbar;\t\t\t#kN\n", "print \"Horizontal component of resulting Pressure in kN : \",PH\n", "PV = 2*r*l*w+math.pi*r**2/4*l*w;\t\t\t#kN\n", "print \"Verticalal component of resulting Pressure in kN : %.3f\"%PV\n", "IG = (l*r**3)/12;\t\t\t#in m**4\n", "h_bar = IG/A/xbar+xbar;\t\t\t#in meter\n", "print \"Position of centre of horizontal component of pressure in meter : %.3f\"%h_bar\n", "x = (2*r+math.pi*r**2/4*(4*r/3/math.pi))/(2*r+math.pi*r**2/4);\t\t\t#meter\n", "P = math.sqrt(PH**2+PV**2);\t\t\t#kN\n", "print \"Resultant pressure in kN : %.3f\"%P\n", "theta = math.degrees(math.atan(PV/PH));\t\t\t#degree\n", "print \"Direction of resultant pressure in degree : %.2f\"%theta\n", "\n", "# note : rounding off error" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Horizontal component of resulting Pressure in kN : 235.44\n", "Verticalal component of resulting Pressure in kN : 280.236\n", "Position of centre of horizontal component of pressure in meter : 3.111\n", "Resultant pressure in kN : 366.011\n", "Direction of resultant pressure in degree : 49.96\n" ] } ], "prompt_number": 23 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.22 Page No : 69" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "\t\t\t\n", "# Variables :\n", "A = 2.*1;\t\t\t#m**2\n", "xbar = 2+2./2;\t\t\t#meter\n", "w = 9.81;\t\t\t#kN/m**2\n", "\n", "# Calculations and Results\n", "PH = w*A*xbar;\t\t\t#kN\n", "print \"Horizontal component of resultant Pressure in kN : \",PH\n", "PV = w*(2*2+2*2-math.pi*2**2/4)*1;\t\t\t#kN\n", "print \"Verticalal component of resultant Pressure in kN : %.3f\"%PV\n", "P = math.sqrt(PH**2+PV**2);\t\t\t#kN\n", "print \"resultant pressure in kN : %.3f\"%P\n", "theta = math.degrees(math.atan(PV/PH));\t\t\t#degree\n", "print \"Direction of resultant pressure in degree : %.2f\"%theta\n", "\n", "# note : rounding ogg error" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Horizontal component of resultant Pressure in kN : 58.86\n", "Verticalal component of resultant Pressure in kN : 47.661\n", "resultant pressure in kN : 75.737\n", "Direction of resultant pressure in degree : 39.00\n" ] } ], "prompt_number": 26 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.23 Page No : 70" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "\t\t\t\n", "# Variables :\n", "ABbar = math.sqrt(2)*4;\t\t\t#meter\n", "xbar = ABbar/2;\t\t\t#meter\n", "\n", "# Calculations and Results\n", "A = ABbar*1;\t\t\t#m**2\n", "w = 9.81;\t\t\t#kN/m**2\n", "PH = w*A*xbar;\t\t\t#kN\n", "print \"Horizontal component of resultant Pressure in kN : \",PH\n", "hbar = 2./3*ABbar;\t\t\t#meter\n", "print \"Position of horizontal component of pressure is \",round(hbar,3),\" meter below free water surface.\"\n", "PV = w*(math.pi*4**2/4-4*4./2)*1;\t\t\t#kN\n", "print \"Verticalal component of resultant Pressure in kN : %.3f\"%PV\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Horizontal component of resultant Pressure in kN : 156.96\n", "Position of horizontal component of pressure is 3.771 meter below free water surface.\n", "Verticalal component of resultant Pressure in kN : 44.796\n" ] } ], "prompt_number": 27 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3.24 Page No : 74" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\t\t\t\n", "# Variables :\n", "h = 24.;\t\t\t#meter\n", "b = 15.;\t\t\t#meter\n", "g = 9.81;\t\t\t#gravity consmath.tant\n", "Wm = 2000.*g;\t\t\t#N/m**3\n", "W = b*h/2*Wm;\t\t\t#N\n", "w = 9.81;\t\t\t#kN/m**2\n", "\n", "# Calculations and Results\n", "PH = w*20**2/2.*1000;\t\t\t#N\n", "y = PH/W*20/3+5;\t\t\t#meter\n", "e = y-b/2;\t\t\t#meter\n", "MaxStress = W/b*(1+6*e/b);\t\t\t#N/m**2\n", "print \"Maximum stress in N/m**2 : \",MaxStress\n", "MinStress = W/b*(1-6*e/b);\t\t\t#N/m**2\n", "print \"Minimum stress in N/m**2 : \",MinStress\n", "\n", "\n", "#Answer in the book is slightly differ due to limited accuracy used in the book as compared to PYTHON.\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Maximum stress in N/m**2 : 348800.0\n", "Minimum stress in N/m**2 : 122080.0\n" ] } ], "prompt_number": 28 } ], "metadata": {} } ] }