{ "metadata": { "name": "MP-10" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": "Statistical Physics" }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": "Example 10.2 Page 307" }, { "cell_type": "code", "collapsed": false, "input": "#initiation of variable\nfrom math import sqrt\n#The solution is purely theoretical and involves a lot of approximations.\nprint\"The value of shift in frequency was found out to be delf=7.14*fo*10^-7*sqrt(T) for a star composing of hydrogen atoms at a temperature T.\";\nT=6000.0; #temperature for sun\ndelf=7.14*10**-7*sqrt(T);#change in frequency\n\n#result\nprint\"The value of frequency shift for sun(at 6000 deg. temperature) comprsing of hydrogen atoms is\",delf,\" times the frequency of the light.\"", "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": "The value of shift in frequency was found out to be delf=7.14*fo*10^-7*sqrt(T) for a star composing of hydrogen atoms at a temperature T.\nThe value of frequency shift for sun(at 6000 deg. temperature) comprsing of hydrogen atoms is 5.53062021838e-05 times the frequency of the light.\n" } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": "Example 10.3 Page 309" }, { "cell_type": "code", "collapsed": false, "input": "#initiation of variable\nfrom math import sqrt,pi, exp, log\nkT=0.0252;E=10.2 # at room temperature, kT=0.0252 standard value and given value of E\n\n#calculation\nn2=2;n1=1; g2=2*(n2**2);g1=2*(n1**2); #values for ground and excited states\nt=(g2/g1)*exp(-E/kT); #fraction of atoms\n\n#result\nprint\"The number of hydrogen atoms required is %.1e\" %(1.0/t),\" which weighs %.1e\" %((1/t)*(1.67*10**-27)),\"Kg\"\n\n#partb\nt=0.1/0.9;k=8.65*10**-5 #fracion of atoms in case-2 is given\nT=-E/(log(t/(g2/g1))*k); #temperature\n\n#result\nprint\"The value of temperature at which 1/10 atoms are in excited state in K is %.1e\" %round(T,3);", "language": "python", "metadata": {}, "outputs": [ { "ename": "TypeError", "evalue": "can't multiply sequence by non-int of type 'float'", "output_type": "pyerr", "traceback": [ "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m\n\u001b[1;31mTypeError\u001b[0m Traceback (most recent call last)", "\u001b[1;32m\u001b[0m in \u001b[0;36m\u001b[1;34m()\u001b[0m\n\u001b[0;32m 8\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m 9\u001b[0m \u001b[1;31m#result\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m---> 10\u001b[1;33m \u001b[1;32mprint\u001b[0m\u001b[1;34m\"The number of hydrogen atoms required is %.1e\"\u001b[0m \u001b[1;33m%\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;36m1.0\u001b[0m\u001b[1;33m/\u001b[0m\u001b[0mt\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m,\u001b[0m\u001b[1;34m\" which weighs %.1e\"\u001b[0m \u001b[1;33m%\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;36m1\u001b[0m\u001b[1;33m/\u001b[0m\u001b[0mt\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m*\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;36m1.67\u001b[0m\u001b[1;33m*\u001b[0m\u001b[1;36m10\u001b[0m\u001b[1;33m**\u001b[0m\u001b[1;33m-\u001b[0m\u001b[1;36m27\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m,\u001b[0m\u001b[1;34m\"Kg\"\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m 11\u001b[0m \u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m 12\u001b[0m \u001b[1;31m#partb\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n", "\u001b[1;31mTypeError\u001b[0m: can't multiply sequence by non-int of type 'float'" ] }, { "output_type": "stream", "stream": "stdout", "text": "The number of hydrogen atoms required is 1.5e+175" } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": "Example 10.4 Page 311" }, { "cell_type": "code", "collapsed": false, "input": "#initiation of variable\nfrom math import log\n#theoritical part a\nprint'The energy of interaction with magnetic field is given by uB and the degeneracy of the states are +-1/2 which are identical.\\nThe ratio is therefore pE2/pE1 which gives e^(-2*u*B/k*T)';\n#partb\nuB=5.79*10**-4; #for a typical atom\nt=1.1;k=8.65*10**-5; #ratio and constant k\n\n#calculation\nT=2*uB/(log(t)*k); #temperature\n\n#result\nprint\"The value of temperature ar which the given ratio exists in K is\",round(T,3);", "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": "The energy of interaction with magnetic field is given by uB and the degeneracy of the states are +-1/2 which are identical.\nThe ratio is therefore pE2/pE1 which gives e^(-2*u*B/k*T)\nThe value of temperature ar which the given ratio exists in K is 140.46\n" } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": "Example 10.5 Page 313" }, { "cell_type": "code", "collapsed": false, "input": "#initiation of variable\nfrom math import pi\np=0.971; A=6.023*10**23; m=23.0; # various given values and constants\n\n#calculation\nc= (p*A/m)*10**6; # atoms per unit volume\nhc=1240.0; mc2=0.511*10**6; # hc=1240 eV.nm\nE= ((hc**2)/(2*mc2))*(((3/(8*pi))*c)**(2.0/3)); #value of fermi energy\n\n#result\nprint\"The fermi energy for sodium is\",round(E*10**-18,4),\"eV\";#multiply by 10^-18 to convert metres^2 term to nm^2", "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": "The fermi energy for sodium is 3.1539 eV\n" } ], "prompt_number": 12 } ], "metadata": {} } ] }