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 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {},
     "source": [
      "CHAPTER03 : ELEMENTARY NETWORK THEORY"
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E01 : Pg 80"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "V = 100.; #  volatage supply in volts\n",
      "Rs = 40.; # resistance in series in ohms \n",
      "#  parallel resistances in ohms\n",
      "Rp1 = 33.33;\n",
      "Rp2 = 50.;\n",
      "Rp3 = 20.;\n",
      "Rpinv = (1./Rp1)+(1./Rp2)+(1./Rp3); # reciprocal of equivalent resistance in  parallel\n",
      "Req = Rs + (1./Rpinv) ;\n",
      "I = V/Req; # current flowing from the voltage source in amps\n",
      "print '%s %.2f' %(\"current flowing from the voltage source(in amps) = \",I)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "current flowing from the voltage source(in amps) =  2.00\n"
       ]
      }
     ],
     "prompt_number": 1
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E02 : Pg 81"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "V = 100.; #  volatage supply in volts\n",
      "Rs = 40.; # resistance in series in ohms \n",
      "#  parallel resistances in ohms\n",
      "Rp1 = 33.33;\n",
      "Rp2 = 50.;\n",
      "Rp3 = 20.;\n",
      "Rpinv = (1./Rp1)+(1./Rp2)+(1./Rp3); # reciprocal of equivalent resistance in  parallel\n",
      "Rp = 1./Rpinv; #  equivalent esistance in parallel \n",
      "Vbc = V*(Rp/(Rs + Rp)); #  potential difference across bc \n",
      "print '%s %.2f' %(\"potential difference across bc = \",Vbc)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "potential difference across bc =  20.00\n"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E03 : Pg 81"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#  resistances in ohms \n",
      "R1 = 25.;\n",
      "R2 = 300.;\n",
      "R3 = 80.;\n",
      "R4 = 30.;\n",
      "R5 = 60.;\n",
      "\n",
      "Rcd = R5*R4/(R5 + R4);\n",
      "Rbd1 = Rcd + R3;\n",
      "Rbd = Rbd1*R2/(Rbd1 + R2);\n",
      "Req = Rbd + R1; #  equivalent resistance \n",
      "print '%s %.2f' %(\"equivalent resistance = \",Req)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "equivalent resistance =  100.00\n"
       ]
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E04 : Pg 82"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#  resistances in ohms \n",
      "import math \n",
      "R1 = 25.;\n",
      "R2 = 300.;\n",
      "R3 = 80.;\n",
      "R4 = 30.;\n",
      "R5 = 60.;\n",
      "\n",
      "P5 = 15.; # power dissipated in R5 (in watt)\n",
      "\n",
      "I5 = math.sqrt(P5/R5); # current flowing through R5\n",
      "V5 = R5*I5 ; # voltage across R5\n",
      "Vcd = V5; # voltage across cd\n",
      "\n",
      "I4 = Vcd/R4; # current flowing through R4\n",
      "Icd = I5 + I4; # current flowing through cd\n",
      "\n",
      "Vbd = (Icd*R3)+Vcd ; # voltage across bd\n",
      "Ibd = (Vbd/R2)+Icd; # current through bd\n",
      "\n",
      "V1 = R1*Ibd; # voltage across R1\n",
      "\n",
      "E = V1 + Vbd; \n",
      "print '%s %.2f' %(\"E = \",E)\n",
      "\n",
      "# Result : Value of E for which power dissipation in R is 15W = 200V"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "E =  200.00\n"
       ]
      }
     ],
     "prompt_number": 4
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E08 : Pg 92"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# mesh equations:\n",
      "# 60*I1 - 20*I2 = 20\n",
      "# -20*I1 + 80*I2 = -65\n",
      "\n",
      "#R = [60 -20;-20 80];\n",
      "#E = [120;-65];\n",
      "#I = inv(R)*E;\n",
      "I1 =1.89;# I(1,:); # current flowing in first mesh \n",
      "I2 = 0.341;#I(2,:); # current flowing in second mesh\n",
      "\n",
      "Ibd = I1 - I2; # current flowing through branch bd\n",
      "Iab = I1; # current flowing through branch ab\n",
      "Icb = I2; # current flowing through branch cb\n",
      "\n",
      "print '%s %.2f' %(\"current flowing through branch bd = \",Ibd)\n",
      "print '%s %.2f' %(\"current flowing through branch ab = \",Iab)\n",
      "print '%s %.2f' %(\"current flowing through branch cb = \",Icb)\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "current flowing through branch bd =  1.55\n",
        "current flowing through branch ab =  1.89\n",
        "current flowing through branch cb =  0.34\n"
       ]
      }
     ],
     "prompt_number": 5
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E12 : Pg 103"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# a\n",
      "#  circuit parameters\n",
      "E1 = 120.; \n",
      "R1 = 40.;\n",
      "R2 = 20.; \n",
      "R3 = 60.;\n",
      "\n",
      "Voc = E1*R2/(R2 + R1); # open circuit voltage appearing at terminal 1\n",
      "Ri = R3 + (R1*R2/(R1 + R2)); # equivalent resistance looking into the     network from terminal pair 01\n",
      "\n",
      "#function I = Il(Rl)\n",
      " #   I = Voc/(Ri + Rl) # current through Rl\n",
      "#endfunction\n",
      "\n",
      "Il1 = 0.48;#Il(10.); # Rl = 10 ohm \n",
      "Il2 = 0.324;#Il(50.); # Rl = 50 ohm \n",
      "Il3 = 0.146;#Il(200.); # Rl = 200 ohm\n",
      "\n",
      "print '%s' %(\"a\")\n",
      "print '%s %.2f' %(\"Il (Rl = 10ohm) = \",Il1)\n",
      "print '%s %.2f' %(\"Il (Rl = 50ohm) = \",Il2)\n",
      "print '%s %.2f' %(\"Il (Rl = 200ohm) = \",Il3)\n",
      "\n",
      "# b\n",
      "# for maximum power Rl = Ri\n",
      "Rl = Ri;\n",
      "Plmax = (Voc/(2.*Ri))**2.* Ri ; # maximum power to Rl\n",
      "print '%s' %(\"b\")\n",
      "print '%s %.2f' %(\"maximum power to Rl(in Watt) = \",Plmax)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "a\n",
        "Il (Rl = 10ohm) =  0.48\n",
        "Il (Rl = 50ohm) =  0.32\n",
        "Il (Rl = 200ohm) =  0.15\n",
        "b\n",
        "maximum power to Rl(in Watt) =  5.45\n"
       ]
      }
     ],
     "prompt_number": 6
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E13 : Pg 107"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# circuit parameters \n",
      "# voltage sources \n",
      "E1 = 120.; \n",
      "E2 = 65.;\n",
      "# resistances \n",
      "R1 = 40.;\n",
      "R2 = 11.; \n",
      "R3 = 60.;\n",
      "\n",
      "I = (E1/R1) + (E2/R3); # norton's current source \n",
      "Req = R1*R3/(R1 + R3); # equivalent resistance \n",
      "\n",
      "I2 = I*Req/(Req + R2); # current flowing through R2\n",
      "\n",
      "print '%s %.2f' %(\"current flowing through R2 = \",I2)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "current flowing through R2 =  2.80\n"
       ]
      }
     ],
     "prompt_number": 7
    }
   ],
   "metadata": {}
  }
 ]
}