{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# Chapter 15 Kinetics of a Particle : Impulse and Momentum" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Ex 15.1 Page No 607" ] }, { "cell_type": "code", "execution_count": 1, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "v2 = 14.1 m/s\n", "NC = 839.6 N\n" ] } ], "source": [ "# Ex 15.1\n", "import math\n", "\n", "# Variable Declaration\n", "ws = 100 #[kilogram]\n", "F = 200 #[Newton]\n", "theta = 45 #[degrees]\n", "\n", "# Calculation\n", "v2 = round(F*10*math.cos(math.pi*theta/180)/100,1) #[meters per second]\n", "NC = round((9.81*ws*10-F*10*math.sin(math.pi*theta/180))/10,1) #[Newtons]\n", "\n", "# Result\n", "print\"v2 = \",(v2),\"m/s\"\n", "print\"NC = \",(NC),\"N\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Ex 15.2 Page No 608" ] }, { "cell_type": "code", "execution_count": 3, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "v2 = 7.67 m/s\n", "NC = 433.0 N\n" ] } ], "source": [ "# Ex 15.2\n", "import math\n", "\n", "# Calculation\n", "# Using +ΣFy = 0\n", "NC = round(500*math.cos(math.pi*30/180),1) #[Newtons]\n", "v2 = round((50.97+100-0.6*NC+500)/50.97,2) #[meters per second]\n", "\n", "# Result\n", "print\"v2 = \",(v2),\"m/s\"\n", "print\"NC = \",(NC),\"N\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Ex 15.3 Page No 609" ] }, { "cell_type": "code", "execution_count": 12, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "vB2 = 35.8 m/s\n", "TB = 19.2 N\n" ] } ], "source": [ "# Ex 15.3\n", "import numpy as np\n", "from __future__ import division\n", "\n", "# Calculation\n", "a = np.array([[-(1/2)*3,2*6], [5,6]])\n", "b = np.array([3*9.81*6,5*9.81*6])\n", "x = np.linalg.solve(a, b)\n", "vB2 = round(x[0],1) #[meters per second]\n", "TB = round(x[1],1) #[Newtons]\n", "\n", "# Result\n", "print\"vB2 = \",(vB2),\"m/s\"\n", "print\"TB = \",(TB),\"N\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Ex 15.4 Page No 616" ] }, { "cell_type": "code", "execution_count": 14, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "v2 = 0.5 m/s\n", "Favg = 18.75 kN\n" ] } ], "source": [ "# Ex 15.4\n", "\n", "# Calculation\n", "# Part(a)\n", "v2 = (15000*1.5-12000*0.75)/27000 #[meters per second]\n", "# Part(b)\n", "Favg = (15000*1.5-15000*0.5)/0.8 #[Newtons]\n", "\n", "# Result\n", "print\"v2 = \",(v2),\"m/s\"\n", "print\"Favg = \",(Favg/1000),\"kN\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Ex 15.5 Page No 617" ] }, { "cell_type": "code", "execution_count": 17, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "vC2 = 4.0 m/s\n", "Favg = 66.67 kN\n" ] } ], "source": [ "# Ex 15.5\n", "\n", "# Calculation\n", "# Part(a)\n", "vC2 = 4*500/500 #[meters per second]\n", "# Part(b)\n", "Favg = 4*500/0.03 #[Newtons]\n", "\n", "# Result\n", "print\"vC2 = \",(vC2),\"m/s\"\n", "print\"Favg = \",round((Favg/1000),2),\"kN\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Ex 15.6 Page No 618" ] }, { "cell_type": "code", "execution_count": 20, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "vT2 = 2.63 m/s\n" ] } ], "source": [ "# Ex 15.6\n", "\n", "# Calculation\n", "vT2 = round((350*10**(3)*3)/(350*10**(3)+50*10**(3)),2) #[meters per second]\n", "\n", "# Result\n", "print\"vT2 = \",(vT2),\"m/s\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Ex 15.7 Page No 619" ] }, { "cell_type": "code", "execution_count": 5, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Impulse = 682.9 N.s\n" ] } ], "source": [ "# Ex 15.7\n", "import math\n", "from __future__ import division\n", "\n", "# Variable Declaration\n", "mH = 300 #[kilogram]\n", "mP = 800 #[kilogram]\n", "\n", "# Calculation\n", "# Using conservation of energy\n", "vH1 = round(math.sqrt((mH*9.81*0.5)/((1/2)*mH)),2) #[meters per second]\n", "# Using conservation of momentum\n", "v2 = (mH*3.13)/(mH+mP) #[meters per second]\n", "# Using Principle of Impulse and Momentum\n", "Impulse = round(300*vH1-300*v2,1) #[Newtons second]\n", "\n", "# Result\n", "print\"Impulse = \",(Impulse),\"N.s\"\n" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Ex 15.9 Page No 627" ] }, { "cell_type": "code", "execution_count": 24, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "Energy_loss = -33.15 J\n" ] } ], "source": [ "# Ex 15.9\n", "import numpy as np\n", "from __future__ import division\n", "\n", "# Calculation\n", "# Using conservation of energy\n", "vA1 = round(math.sqrt((6*9.81*1)/((1/2)*6)),2)\n", "# Using Conservation of Momentum and formula for coefficient of restitution\n", "a = np.array([[1,3], [1,-1]])\n", "b = np.array([4.43,-2.215])\n", "x = np.linalg.solve(a, b)\n", "vA2 = round(x[0],3) #[meters per second]\n", "vB2 = round(x[1],2) #[meters per second]\n", "Energy_loss = round((1/2)*18*vB2**(2)+(1/2)*6*vA2**(2)-(1/2)*6*vA1**(2),2) #[Joules]\n", "\n", "# Result\n", "print\"Energy_loss = \",(Energy_loss),\"J\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Ex 15.10 Page No 628" ] }, { "cell_type": "code", "execution_count": 6, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "s3 = 237.0 mm\n" ] } ], "source": [ "# Ex 15.10\n", "from __future__ import division\n", "import numpy as np\n", "import math\n", "\n", "# Variable Declaration\n", "wB = 1.5 #[kilogram]\n", "k = 800 #[Newton meter]\n", "\n", "# Calculation\n", "# Using Principle of conservation of energy\n", "vB1 = round(math.sqrt((-wB*9.81*1.25+(1/2)*k*0.25**(2))/((1/2)*1.5)),2) #[meters per second]\n", "# Using Principle of coefficient of restitution\n", "vB2 = 0.8*(0-2.97)+0 #[meters per second]\n", "# Using Principle of conservation of energy\n", "coeff = [400,-14.72,-18.94]\n", "# Taking positive root\n", "s3 = round(np.roots(coeff)[0],3) #[meters]\n", "\n", "# Result\n", "print\"s3 = \",(s3*1000),\"mm\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Ex 15.11 Page No 629" ] }, { "cell_type": "code", "execution_count": 32, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "vAx2 = -1.26 m/s\n", "vBx2 = 1.22 m/s\n", "vAy2 = 1.5 m/s\n", "vBy2 = -0.71 m/s\n" ] } ], "source": [ "# Ex 15.11\n", "import numpy as np\n", "import math\n", "\n", "# Calculation\n", "vAx1 = round(3*math.cos(math.pi*30/180),2)\n", "vAy1 = round(3*math.sin(math.pi*30/180),2)\n", "vBx1 = round(-1*math.cos(math.pi*45/180),2)\n", "vBy1 = round(-1*math.sin(math.pi*45/180),2)\n", "# Using Conservation of \"x\" Momentum and Coefficient of restitution\n", "a = np.array([[1,2], [-1,1]])\n", "b = np.array([1.18,2.48])\n", "x = np.linalg.solve(a, b)\n", "vAx2 = round(x[0],3) #[meters per second]\n", "vBx2 = round(x[1],2) #[meters per second]\n", "# Using Conservation of \"x\" Momentum\n", "vAy2 = vAy1\n", "vBy2 = vBy1\n", "\n", "# Result\n", "print\"vAx2 = \",(vAx2),\"m/s\"\n", "print\"vBx2 = \",(vBx2),\"m/s\"\n", "print\"vAy2 = \",(vAy2),\"m/s\"\n", "print\"vBy2 = \",(vBy2),\"m/s\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Ex 15.13 Page No 640" ] }, { "cell_type": "code", "execution_count": 7, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "vA2 = 20.0 m/s\n" ] } ], "source": [ "# Ex 15.13\n", "from __future__ import division\n", "\n", "# Variable Declaration\n", "P = 10 #[Newton]\n", "wB = 5 #[kilogram]\n", "\n", "# Calculation\n", "vA2 = ((3/2)*(4**(2)-0**(2))+0.4*P*4)/(wB*0.4) #[meters per second]\n", "\n", "# Result\n", "print\"vA2 = \",(vA2),\"m/s\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Ex 15.14 Page No 641" ] }, { "cell_type": "code", "execution_count": 35, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "UF = 2.31 J\n" ] } ], "source": [ "# Ex 15.14\n", "\n", "# Variable Declaration\n", "v1 = 1 #[meters per second]\n", "r1 = 0.5 #[meters]\n", "r2 = 0.2 #[meters]\n", "vC = 2 #[meters per second]\n", "\n", "# Calculation\n", "# Part(a)\n", "# Using principle of Conservation of Angular Momentum\n", "v2dash = (r1*0.5*v1)/(r2*0.5) #[meters per second]\n", "v2 = round(math.sqrt(2.5**(2)+2**(2)),2) #[meters per second]\n", "# Part(b)\n", "UF = (1/2)*0.5*v2**(2)-(1/2)*0.5*v1**(2) #[Joules]\n", "\n", "# Result\n", "print\"UF = \",(UF),\"J\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Ex 15.15 Page No 642" ] }, { "cell_type": "code", "execution_count": 38, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "vD2doubledash = 0.838 m/s\n" ] } ], "source": [ "# Ex 15.15\n", "import math\n", "from __future__ import division\n", "\n", "# Variable Declaration\n", "vD1 = 1.5 #[meters per second]\n", "kc = 20 #[Newtons per meter]\n", "\n", "# Calculation\n", "# Using principle of Conservation of Angular Momentum\n", "vD2dash = (0.5*2*1.5)/(0.7*2) #[meters per second]\n", "# Using Conservation of Energy\n", "vD2 = round(math.sqrt(((1/2)*2*vD1**(2)-(1/2)*kc*0.2**(2))/((1/2)*2)),2) #[meters per second]\n", "vD2doubledash = round(math.sqrt(vD2**(2)-vD2dash**(2)),3) #[meters per second]\n", "\n", "# Result\n", "print\"vD2doubledash = \",(vD2doubledash),\"m/s\"" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [] } ], "metadata": { "kernelspec": { "display_name": "Python [default]", "language": "python", "name": "python2" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 2 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython2", "version": "2.7.12" } }, "nbformat": 4, "nbformat_minor": 1 }