{ "metadata": { "name": "", "signature": "" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 5, Wave motion and speed of waves in gases" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 1, page 206" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from __future__ import division\n", "# wavelength\n", "#given data :\n", "v=960 # in m/s\n", "n=3600/60 # in per sec\n", "lamda=v/n \n", "print \"The wavelength, lamda = %0.f m \" %lamda" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The wavelength, lamda = 16 m \n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 2, page 206" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Frequency\n", "#given data :\n", "c=3*10**8 # in m/s\n", "lamda=300 # in m\n", "n=c*10**-6/lamda \n", "print \"The frequency, n = %0.f MHz \" %n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The frequency, n = 1 MHz \n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 3, page 208" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# velocity and direction\n", "#y=1.2*sin(3.5*t+0.5*x) #equation\n", "w=3.5 #from equation\n", "k=0.5 #from equation\n", "v=w/k #m/s\n", "print \"wave velocity =\",v,\"m/s and direction of the wave is along negative X-axis\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "wave velocity = 7.0 m/s and direction of the wave is along negative X-axis\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 4, page 209" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from sympy import symbols, pi, sin\n", "#equation of wave propogation\n", "amp=0.02 #m\n", "fr=110 #Hz\n", "v=330 #m/s\n", "w=2*pi*fr #s**-1\n", "k=w/v #constant\n", "t, x = symbols('t x')\n", "y=amp*sin(w*t-k*x) #refrence equation\n", "print \"Equation of wave is\",y" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Equation of wave is 0.02*sin(220*pi*t - 2*pi*x/3)\n" ] } ], "prompt_number": 16 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 5, page 211" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from numpy import pi\n", "#path difference\n", "v=360 #m/s\n", "fr=500 #Hz\n", "h=v/fr #wavelength in metre\n", "ang=60 #degree\n", "angr=ang*(pi/180) #radian\n", "pth=(h)/(2*pi) #metre\n", "print \"Path difference = %0.2f m \" %pth" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Path difference = 0.11 m \n" ] } ], "prompt_number": 17 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6, page 211" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import pi\n", "#path difference\n", "pth=15 #cm\n", "pd=(2*pi)/3 #radians\n", "h=(pth*2*pi)/pd #cm\n", "print \"Wavelength = %0.f cm \" %h" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Wavelength = 45 cm \n" ] } ], "prompt_number": 19 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 8, page 214" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import sin,degrees\n", "from sympy import pi\n", "#displacement ,particle velocity and acceleration\n", "x=200 #cm\n", "a=3 # cm\n", "v=1000#cm/s\n", "n=25\n", "lamda=v/n \n", "y=a*sin(2*pi/lamda*(v*t-x))\n", "\n", "v=1000 #cm/s\n", "n=25 #vibrations\n", "h=v/n #cm\n", "a=3 #cm\n", "t=2 #seconds\n", "vl=2*pi*a*n #cm/s\n", "acc=0 #\n", "print \"Displacement c = %0.f m \" %round(abs(y))\n", "print \"Velocity =\",vl,\"cm/s \" \n", "print \"Acceleration = %0.2f cm/s^2 \" %acc" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Displacement c = 0 m \n", "Velocity = 150*pi cm/s \n", "Acceleration = 0.00 cm/s^2 \n" ] } ], "prompt_number": 62 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9, page 215" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#amplitude,frequency,velocity ,wavelength and speed\n", "#y=5*sin*(4t-0.02x) #given\n", "a=5 #cm \n", "h=(2*pi)/0.02 #\n", "v=0.02*10000 #cm/s\n", "n=v/h #cycles/seconds\n", "print \"Amplitude = %0.2f cm \" %a\n", "print \"Frequency = %0.3f cycles/s \" %n\n", "print \"Velocity = %0.f cm/s \" %v\n", "print \"Wavelength = %0.f cm \" %h\n", "ma1x=a*4 #cm/s\n", "print \"Maximum speed = %0.2f cm/s \" %ma1x" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Amplitude = 5.00 cm \n", "Frequency = 0.637 cycles/s \n", "Velocity = 200 cm/s \n", "Wavelength = 314 cm \n", "Maximum speed = 20.00 cm/s \n" ] } ], "prompt_number": 66 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 10, page 216" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import pi\n", "#wave intensity\n", "nt=1 #watt source\n", "r=1 #n\n", "Is=(nt/(4*pi*r**2)) # joule/sec-m**2\n", "print \"Intensity on the surface = %0.2f J/s-m^2 \" %Is" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Intensity on the surface = 0.08 J/s-m^2 \n" ] } ], "prompt_number": 67 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 14, page 225" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Energy flux \n", "#given data :\n", "A=.10 # in m\n", "w=4 # in per sec\n", "k=0.1 # in per cm\n", "p=1.25*10**3 # in kg/m**3\n", "v=w*10**-2/k # in m/s\n", "n=w/(2*pi) \n", "Ef=2*pi**2*n**2*A**2*p*v \n", "print \"Energy flux of the wave, Ef = %0.f W/m^2 \" %Ef" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Energy flux of the wave, Ef = 40 W/m^2 \n" ] } ], "prompt_number": 69 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 15, page 225" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Energy radiated and energy current\n", "#given data :\n", "p=1.29 # in kg/m**3\n", "a=.15*10**-2 # in m/s\n", "n=76 # in Hz\n", "E=2*pi**2*n**2*a**2*p \n", "print \"(a) Energy radiated, E = %0.3f J/m^3 \" %E\n", "v=332 # in m/s\n", "Ev=E*v \n", "print \"(b) The energy current, Ev = %0.2f W/s \" %Ev\n", "# energy current is calculated wrong in the textbook" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "(a) Energy radiated, E = 0.331 J/m^3 \n", "(b) The energy current, Ev = 109.87 W/s \n" ] } ], "prompt_number": 71 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 16, page 234" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Pressure amplitude, Energy density and energy flux\n", "#given data :\n", "a=10**-5 # in m\n", "n=500 # in per sec\n", "p=1.29 # in kg/m**3\n", "v=340 # in m/s\n", "Pa=2*pi*a*n*v*p \n", "print \"(i) Pressure amplitude, Pa = %0.1f N/m^2 \" %Pa\n", "Ed=2*pi**2*a**2*n**2*p \n", "print \"(ii) Energy density, Ed = %0.1e J/m^3 \"%Ed\n", "Ef=2*pi**2*a**2*n**2*p*v \n", "print \"(iii) The energy flux, Ef = %0.2f J/m^2-s \" %Ef" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "(i) Pressure amplitude, Pa = 13.8 N/m^2 \n", "(ii) Energy density, Ed = 6.4e-04 J/m^3 \n", "(iii) The energy flux, Ef = 0.22 J/m^2-s \n" ] } ], "prompt_number": 74 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 17, page 235" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# Pressure \n", "#given data :\n", "gama=1.4 \n", "u=10**-3 # in m/s\n", "v=340 # in m/s\n", "P=10**5 # in N/m**2\n", "p=gama*P*u/v \n", "print \"The pressure, p = %0.2f N/m^2 \" %p" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The pressure, p = 0.41 N/m^2 \n" ] } ], "prompt_number": 77 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 18, page 238" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import sqrt\n", "#speed\n", "sa=332 #m/s\n", "pa=16 #density of air\n", "ph=1 #density of hydrogen\n", "vn=sa*sqrt(pa/ph) #m/s\n", "t1=0 #degree celsius\n", "t2=546 #degree celsius\n", "t1k=0+273 #kelvin\n", "t2k=t2+273 #kelvin\n", "v2=vn*sqrt(t2k/t1k) #m/s\n", "print \"Speed of sound in first case = %0.f m/s \" %vn\n", "print \"speed of sound in second case is = %0.f m/s\" %v2" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Speed of sound in first case = 1328 m/s \n", "speed of sound in second case is = 2300 m/s\n" ] } ], "prompt_number": 80 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 19, page 239" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#temperature\n", "t1=0 #degree celsius\n", "t1k=t1+273 #kelvin\n", "rt=2 #\n", "tk=rt**2*t1k #Kelvin\n", "t=tk-273 #degree celsius\n", "print \"Temperature = %0.f degree-celsius \" %t" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Temperature = 819 degree-celsius \n" ] } ], "prompt_number": 81 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 20, page 239" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#temperature\n", "rtd=16/14 #ratio of densities\n", "tk=15+273 #degree celsius\n", "x=(tk*rtd)-273 #degree celsius\n", "print \"Temperature = %0.2f degree-celsius \" %x" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Temperature = 56.14 degree-celsius \n" ] } ], "prompt_number": 82 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 21, page 240" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#speed\n", "rt=4/1 #\n", "ss=332 #m/s\n", "rd=32/28 #ratio of densities\n", "rt1=((1+(1/rt)*rd)/(1+(1/rt))) #\n", "v1=ss*sqrt(rt1) #m/s\n", "print \"Speed of sound in nitrogen = %0.1f m/s \" %v1" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Speed of sound in nitrogen = 336.7 m/s \n" ] } ], "prompt_number": 84 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 22, page 241" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#speed\n", "gm=1.41 #\n", "vs=330 #m/s\n", "vrms=sqrt(3/gm)*vs #m/s\n", "print \"Root mean square velocity of molecules of gas = %0.f m/s \" %vrms" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Root mean square velocity of molecules of gas = 481 m/s \n" ] } ], "prompt_number": 86 } ], "metadata": {} } ] }