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+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:0a1f9cbfac6e4a80fe362c0012a4a307feac15a79ecc69bd2a9d9a5220fc3bbc"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "Chapter21-Magnetic Materials"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Ex1-pg612"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "##Example 21.1\n",
+      "##calculation of magnetizing force and relative permeability\n",
+      "\n",
+      "##given values\n",
+      "M=2300.;##magnetization in A/m\n",
+      "B=.00314;##flux density in Wb/m**2\n",
+      "u=12.57*10**-7.;##permeability in H/m\n",
+      "\n",
+      "##calculation\n",
+      "H=(B/u)-M;\n",
+      "print'%s %.2f %s'%('magnetizing force(in A/m)is ',H,'');\n",
+      "Ur=B/(u*H);\n",
+      "print'%s %.2f %s'%('relative permeability is',Ur,'')\n"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "magnetizing force(in A/m)is  198.01 \n",
+        "relative permeability is 12.62 \n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Ex2-pg613"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "##Example 21.2\n",
+      "##calculation of magnetization and magnetic flux density\n",
+      "\n",
+      "##given values\n",
+      "H=10**5;##external field  in A/m\n",
+      "X=5*10**-5;##susceptibility \n",
+      "u=12.57*10**-7;##permeability in H/m\n",
+      "\n",
+      "##calculation\n",
+      "M=X*H;\n",
+      "print'%s %.2f %s'%('magnetization (in A/m)is ',M,'');\n",
+      "B=u*(M+H);\n",
+      "print'%s %.2f %s'%('magnetic flux density (in wb/m^2) is',B,'')\n"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "magnetization (in A/m)is  5.00 \n",
+        "magnetic flux density (in wb/m^2) is 0.13 \n"
+       ]
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "Ex3-pg615"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      "import math\n",
+      "##Example 21.3\n",
+      "##calculation of relative permeability\n",
+      "\n",
+      "##given values\n",
+      "\n",
+      "X=3.7*10**-3;##susceptibility at 300k\n",
+      "T=300;##temp in K\n",
+      "T1=200;##temp in K\n",
+      "T2=500;##temp in K\n",
+      "\n",
+      "##calculation\n",
+      "C=X*T;##curie constant\n",
+      "XT1=C/T1;\n",
+      "print'%s %.4f %s'%('relative permeability at T1 is ',XT1,'');\n",
+      "XT2=C/T2;\n",
+      "print'%s %.3f %s'%('relative permeability at T2 is',XT2,'')\n"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "relative permeability at T1 is  0.0056 \n",
+        "relative permeability at T2 is 0.002 \n"
+       ]
+      }
+     ],
+     "prompt_number": 3
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
+\ No newline at end of file