{ "metadata": { "name": "", "signature": "sha256:be9a21f00f98f6eae4cb352ab1396adae89de508dceae8166d48e690d1fe887a" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "8: X-Rays" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 8.1, Page number 210" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "theta = 15; #angle of reflection(degrees)\n", "d = 2.5; #atomic spacing(angstrom)\n", "n = 1; #first order\n", "\n", "#Calculation\n", "d = d*10**-10; #atomic spacing(m)\n", "theta = theta*math.pi/180; #angle of reflection(radian)\n", "lamda = 2*d*math.sin(theta)/n; #wavelength of X-rays(m)\n", "\n", "#Result\n", "print \"wavelength of X-rays is\",round(lamda/1e-10,3),\"*10**-10 m\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "wavelength of X-rays is 1.294 *10**-10 m\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 8.2, Page number 211" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "two_theta = 20; #angle of reflection(degrees)\n", "d = 2.82; #atomic spacing(angstrom)\n", "n = 1; #first order\n", "\n", "#Calculation\n", "theta = two_theta/2;\n", "theta = theta*math.pi/180; #angle of reflection(radian)\n", "lamda = 2*d*math.sin(theta)/n; #wavelength of X-rays(angstrom)\n", "lamda = math.ceil(lamda*10**4)/10**4; #rounding off to 4 decimals\n", "\n", "#Result\n", "print \"wavelength of X-rays is\",lamda,\"angstrom\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "wavelength of X-rays is 0.9794 angstrom\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 8.3, Page number 211" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "lamda = 10; #wavelength(pm)\n", "phi = 45; #scattering angle(degrees)\n", "h = 6.62*10**-34; #planck's constant(m**2 kg/s)\n", "m0 = 9.1*10**-31; #mass(kg)\n", "c = 3*10**8; #velocity of light(m/s)\n", "ev = 6.24*10**18; #conversion factor from J to eV\n", "\n", "#Calculation\n", "phi = phi*math.pi/180; #scattering angle(radian)\n", "a = h/(m0*c); #value of constant(m)\n", "a = a*10**12; #value of constant(pm)\n", "lamda_dash = lamda+(a*(1-math.cos(phi))); #wavelength of X-rays(pm)\n", "lamda_dash = math.ceil(lamda_dash*10**2)/10**2; #rounding off to 2 decimals\n", "lamdadash = lamda+(2*a); #maximum wavelength of scattered x-rays(pm)\n", "lamdadash = math.ceil(lamdadash*10)/10; #rounding off to 1 decimal\n", "KE = h*c*((1/lamda)-(1/lamdadash))/(10**-12); #maximum kinetic energy(J)\n", "KE = KE*ev; #maximum kinetic energy(eV)\n", "KE = KE*10**-3; #maximum kinetic energy(KeV)\n", "KE = math.ceil(KE*10)/10; #rounding off to 1 decimal\n", "\n", "#Result\n", "print \"wavelength of X-rays scattered is\",lamda_dash,\"pm\"\n", "print \"maximum wavelength of scattered x-rays is\",lamdadash,\"pm\"\n", "print \"maximum kinetic energy is\",KE,\"KeV\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "wavelength of X-rays scattered is 10.72 pm\n", "maximum wavelength of scattered x-rays is 14.9 pm\n", "maximum kinetic energy is 40.8 KeV\n" ] } ], "prompt_number": 21 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 8.4, Page number 212" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "h = 6.62*10**-34; #planck's constant(m**2 kg/s)\n", "m0 = 9.1*10**-31; #mass(kg)\n", "c = 3*10**8; #velocity of light(m/s)\n", "phi = 180; #scattering angle(degrees)\n", "\n", "#Calculation\n", "phi = phi*math.pi/180; #scattering angle(radian)\n", "a = h/(m0*c); #value of constant(m)\n", "a = a*10**10; #value of constant(angstrom)\n", "delta_lamda = a*(1-math.cos(phi)); #change in wavelength(angstrom)\n", "delta_lamda = math.ceil(delta_lamda*10**4)/10**4; #rounding off to 4 decimals\n", "\n", "#Result\n", "print \"change in wavelength of photon is\",delta_lamda,\"angstrom\"\n", "print \"answer in the book varies due to rounding off errors\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "change in wavelength of photon is 0.0485 angstrom\n", "answer in the book varies due to rounding off errors\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 8.5, Page number 212" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "h = 6.62*10**-34; #planck's constant(m**2 kg/s)\n", "m0 = 9.1*10**-31; #mass(kg)\n", "c = 3*10**8; #velocity of light(m/s)\n", "phi = 90; #scattering angle(degrees)\n", "\n", "#Calculation\n", "phi = phi*math.pi/180; #scattering angle(radian)\n", "a = h/(m0*c); #value of constant(m)\n", "a = a*10**10; #value of constant(angstrom)\n", "lamda = a*(1-math.cos(phi)); #wavelength(angstrom)\n", "lamda = math.ceil(lamda*10**5)/10**5; #rounding off to 5 decimals\n", "E = h*c/(lamda*10**-10); #energy of photon(J)\n", "\n", "#Result\n", "print \"wavelength of the photon is\",lamda,\"angstrom\"\n", "print \"energy of the incident photon is\",round(E/1e-14,4),\"*10**-14 J\"\n", "print \"answer for energy of incident photon is wrong in the book\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "wavelength of the photon is 0.02425 angstrom\n", "energy of the incident photon is 8.1897 *10**-14 J\n", "answer for energy of incident photon is wrong in the book\n" ] } ], "prompt_number": 14 } ], "metadata": {} } ] }