{ "metadata": { "name": "", "signature": "sha256:e2ed8f14e9384f32112bf8b476c63d65b4316d749e72b2c8fa7bc92794bf7f8a" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Magnetic materials" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 10.1, Page number 305" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "\n", "#importing modules\n", "import math\n", "\n", "#Variable declaration\n", "H=10**6; #magnetic field strength in A/m\n", "chi=0.5*10**-5; #magnetic susceptibility\n", "\n", "#Calculation\n", "mew0=4*math.pi*10**-7;\n", "M=chi*H;\n", "B=mew0*(M+H);\n", "B=math.ceil(B*10**3)/10**3; #rounding off to 3 decimals\n", "\n", "#Result\n", "print(\"intensity of magnetisation in A/m is\",M);\n", "print(\"flux density in Wb/m^2 is\",B);\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "('intensity of magnetisation in A/m is', 5.0)\n", "('flux density in Wb/m^2 is', 1.257)\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 10.2, Page number 306" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "#importing modules\n", "import math\n", "\n", "#Variable declaration\n", "A=6.022*10**23; #avagadro number\n", "mew0=4*math.pi*10**-7;\n", "w=58.7; #atomic weight of Ni\n", "B=0.65; #saturation magnetic induction in Wb/m^2\n", "rho=8906; #density in kg/m^3\n", "\n", "#Calculation\n", "rho=rho*10**3; #converting into gm/m^3\n", "N=(rho*A)/w;\n", "mew_m=B/(N*mew0);\n", "#mew_m/(9.27*10^-24) gives mew_m in mewB\n", "mew_m=mew_m/(9.27*10**-24);\n", "mew_m=math.ceil(mew_m*10**3)/10**3; #rounding off to 3 decimals\n", "\n", "#Result\n", "print(\"magnetic moment of Ni is\",mew_m,\"mew_b\");\n", "#that is mew_m=0.61 mew_b" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "('magnetic moment of Ni is', 0.611, 'mew_b')\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 10.3, Page number 306" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "#importing modules\n", "import math\n", "\n", "#Variable declaration\n", "mew_0=4*math.pi*10**-7;\n", "H=1800; #magnetic field in A/m\n", "phi=3*10**-5; #magnetic flux in Wb\n", "A=0.2; #area of cross section in cm^2\n", "\n", "#Calculation\n", "A=A*10**-4; #area in m^2\n", "B=phi/A;\n", "mew_r=B/(mew_0*H);\n", "mew_r=math.ceil(mew_r*10**3)/10**3; #rounding off to 3 decimals\n", "\n", "#Result\n", "print(\"permeability of material is\",mew_r);" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "('permeability of material is', 663.146)\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 10.4, Page number 307" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "#importing modules\n", "import math\n", "\n", "#Variable declaration\n", "mew=18.4; #magnetic moment in mew_b\n", "a=0.835; #lattice parameter in nm\n", "\n", "#Calculation\n", "mew=mew*9.27*10**-24;\n", "a=a*10**-9; #converting nm to m\n", "V=a**3;\n", "M=mew/V;\n", "M=M/10**5;\n", "M=math.ceil(M*10**4)/10**4; #rounding off to 4 decimals\n", "\n", "#Result\n", "print(\"saturation magnetisation in A/m is\",M,\"*10**5\");" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "('saturation magnetisation in A/m is', 2.9299, '*10**5')\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 10.5, Page number 307" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "\n", "#importing modules\n", "import math\n", "\n", "#Variable declaration\n", "mew_0=4*math.pi*10**-7;\n", "H=2*10**5; #magnetic field strength in A/m\n", "mew_r=1.01; #relative permeability\n", "\n", "#Calculation\n", "B=mew_0*mew_r*H;\n", "B=math.ceil(B*10**5)/10**5; #rounding off to 3 decimals\n", "M=(B/mew_0)-H;\n", "M=math.ceil(M*10**2)/10**2; #rounding off to 2 decimals\n", "\n", "#Result\n", "print(\"magnetic flux density in Wb/m^2 is\",B);\n", "print(\"magnetisation in A/m is\",M);\n", "\n", "#answer for magnetisation given in the book is wrong" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "('magnetic flux density in Wb/m^2 is', 0.25385)\n", "('magnetisation in A/m is', 2007.42)\n" ] } ], "prompt_number": 9 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example number 10.6, Page number 307" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "\n", "#importing modules\n", "import math\n", "\n", "#Variable declaration\n", "mew_0=4*math.pi*10**-7;\n", "H=500; #magnetic field strength in A/m\n", "chi=1.2; #susceptibility\n", "\n", "#Calculation\n", "M=chi*H;\n", "B=mew_0*(M+H);\n", "B=B*10**3;\n", "B=math.ceil(B*10**4)/10**4; #rounding off to 4 decimals\n", "\n", "#Result\n", "print(\"magnetic flux density in Wb/m^2 is\",B,\"*10**-3\");" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "('magnetic flux density in Wb/m^2 is', 1.3824, '*10**-3')\n" ] } ], "prompt_number": 14 }, { "cell_type": "code", "collapsed": false, "input": [], "language": "python", "metadata": {}, "outputs": [] } ], "metadata": {} } ] }