{ "metadata": { "name": "" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "

Chapter 15: Single-phase series a.c. circuits

" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 1, page no. 214

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#(a) Calculate the reactance of a coil \n", "#(b) Determine the inductance of the coil.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "L = 0.32;# in Henry\n", "f1 = 50;# in Hz\n", "f2 = 5000;# in Hz\n", "Z = 124;# in ohms\n", "\n", "#calculation:\n", "XL = 2*math.pi*f1*L\n", "L = Z/(2*math.pi*f2)\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)Inductive reactance, XL = \",round(XL,2),\" ohms \\n\"\n", "print \"\\n (b)Inductance L = \",round((L/1E-3),2),\" mH \\n\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)Inductive reactance, XL = 100.53 ohms \n", "\n", "\n", " (b)Inductance L = 3.95 mH " ] } ], "prompt_number": 1 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 2, page no. 214

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate its inductive reactance and the resulting current if connected to\n", "#(a) a 240 V, 50 Hz supply, and (b) a 100 V, 1 kHz supply.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "L = 0.040;# in Henry\n", "V1 = 240;# in volts\n", "V2 = 100;# in volts\n", "f1 = 50;# in Hz\n", "f2 = 1000;# in Hz\n", "\n", "#calculation:\n", "XL1 = 2*math.pi*f1*L\n", "I1 = V1/XL1\n", "XL2 = 2*math.pi*f2*L\n", "I2 = V2/XL2\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)Inductive reactance, XL = \",round( XL1,2),\" ohms and current I = \",round( I1,2),\" A\\n\"\n", "print \"\\n (b)Inductive reactance, XL = \",round( XL2,2),\" ohms and current I = \",round( I2,2),\" A\\n\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)Inductive reactance, XL = 12.57 ohms and current I = 19.1 A\n", "\n", "\n", " (b)Inductive reactance, XL = 251.33 ohms and current I = 0.4 A" ] } ], "prompt_number": 2 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 3, page no. 215

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Determine the capacitive reactance of a capacitor of 10 \u03bcF when connected to a circuit of frequency (a) 50 Hz (b) 20 kHz\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "C = 10E-6;# in Farads\n", "f1 = 50;# in Hz\n", "f2 = 20000;# in Hz\n", "\n", "#calculation:\n", "Xc1 = 1/(2*math.pi*f1*C)\n", "Xc2 = 1/(2*math.pi*f2*C)\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)Capacitive reactance, Xc = \",round( Xc1,2),\" ohms \"\n", "print \"\\n (b)Capacitive reactance, Xc = \",round( Xc2,2),\" ohms \"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)Capacitive reactance, Xc = 318.31 ohms \n", "\n", " (b)Capacitive reactance, Xc = 0.8 ohms " ] } ], "prompt_number": 3 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 4, page no. 215

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Determine the value of its capacitance.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "Z = 40;# in ohms\n", "f = 50;# in Hz\n", "\n", "#calculation:\n", "C = 1/(2*math.pi*f*Z)\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n Capacitance,C = \",round((C/1E-6),2),\" uF \"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " Capacitance,C = 79.58 uF " ] } ], "prompt_number": 4 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 5, page no. 215

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the current taken by a 23 \u03bcF capacitor when connected to a 240 V, 50 Hz supply.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "C = 23E-6;# in Farads\n", "f = 50;# in Hz\n", "V = 240;# in volts\n", "\n", "#calculation:\n", "Xc = 1/(2*math.pi*f*C)\n", "I = V/Xc\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n current I = \",round(I,2),\" A \"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " current I = 1.73 A " ] } ], "prompt_number": 5 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 6, page no. 216

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Find the supply voltage and the phase angle between current and voltage\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "Vr = 12;# in volts\n", "Vl = 5;# in volts\n", "\n", "#calculation:\n", "V = (Vr**2 + Vl**2)**0.5\n", "phi = math.atan(Vl/Vr)\n", "phid = phi*180/math.pi\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n supply voltage V = \",V,\" V, phase angle between current and voltage is \", round(phid,2),\"deg lagging\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " supply voltage V = 13.0 V, phase angle between current and voltage is 22.62 deg lagging" ] } ], "prompt_number": 7 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 7, page no. 216

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate (a) the reactance, (b) the impedance, and (c) the current taken from a 240 V, 50 Hz supply. \n", "#Determine also the phase angle between the supply voltage and current\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "V = 240;# in volts\n", "R = 4;# in ohms\n", "L = 0.00955;# in Henry\n", "f = 50;# in Hz\n", "\n", "#calculation:\n", "XL = 2*math.pi*f*L\n", "Z = (R**2 + XL**2)**0.5\n", "I = V/Z\n", "phid = math.atan(XL/R)*180/math.pi\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)Inductive reactance, XL = \",round(XL,2),\" ohms\"\n", "print \"\\n (b)Impedance, Z = \",round(Z,2),\" ohms\"\n", "print \"\\n (c)Current, I = \",round(I,2),\" A\"\n", "print \"\\n (d)phase angle between the supply voltage and current is \",round(phid,2),\"deg lagging\\n\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)Inductive reactance, XL = 3.0 ohms\n", "\n", " (b)Impedance, Z = 5.0 ohms\n", "\n", " (c)Current, I = 48.0 A\n", "\n", " (d)phase angle between the supply voltage and current is 36.87 deg lagging\n" ] } ], "prompt_number": 8 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 8, page no. 217

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the resistance, impedance, inductive reactance and inductance of the coil.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "Vdc = 12;# in volts\n", "Vac = 240;# in volts\n", "Iac = 20;# in Amperes\n", "Idc = 2;# in Amperes\n", "f = 50;# in Hz\n", "\n", "#calculation:\n", "R = Vdc/Idc\n", "Z = Vac/Iac\n", "XL = (Z**2 - R**2)**0.5\n", "L = XL/(2*math.pi*f)\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)Resistance, R = \",R,\" ohms\"\n", "print \"\\n (b)Impedance, Z = \",Z,\" ohms\"\n", "print \"\\n (c)Inductive reactance, XL = \",round(XL,2),\" ohms\"\n", "print \"\\n (d)Inductance, L = \",round(L,2),\" H\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)Resistance, R = 6.0 ohms\n", "\n", " (b)Impedance, Z = 12.0 ohms\n", "\n", " (c)Inductive reactance, XL = 10.39 ohms\n", "\n", " (d)Inductance, L = 0.03 H" ] } ], "prompt_number": 8 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 9, page no. 217

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate (a) the inductive reactance of the coil, \n", "#(b) the impedance of the circuit, \n", "#(c) the current in the circuit, \n", "#(d) the p.d. across each component, and \n", "#(e) the circuit phase angle.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "R = 200;# in ohms\n", "L = 0.3183;# in henry\n", "V = 240;# in volts\n", "f = 50;# in Hz\n", "\n", "#calculation:\n", "XL = 2*math.pi*f*L\n", "Z = (R**2 + XL**2)**0.5\n", "I = V/Z\n", "VL = I*XL\n", "VR = I*R\n", "phid = math.atan(XL/R)*180/math.pi\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)Inductive reactance, XL = \",round(XL,2),\" ohms\"\n", "print \"\\n (b)Impedance, Z = \",round(Z,2),\" ohms\"\n", "print \"\\n (c)current, I = \",round(I,2),\" A\"\n", "print \"\\n (d)p.d. across Inductor, VL = \",round(VL,2),\" V and p.d. across resistance, VR = \",round(VR,2),\" V\"\n", "print \"\\n (e)circuit phase angle is \",round(phid,2),\" deg lagging\\n\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)Inductive reactance, XL = 100.0 ohms\n", "\n", " (b)Impedance, Z = 223.61 ohms\n", "\n", " (c)current, I = 1.07 A\n", "\n", " (d)p.d. across Inductor, VL = 107.33 V and p.d. across resistance, VR = 214.66 V\n", "\n", " (e)circuit phase angle is 26.56 deg lagging\n" ] } ], "prompt_number": 9 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 10, page no. 218

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#calculate (a) the circuit impedance, \n", "#(b) the current flowing, \n", "#(c) the p.d. across the resistance, \n", "#(d) the p.d. across the inductance and \n", "#(e) the phase angle between voltage and current.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "R = 100;# in ohms\n", "L = 0.2;# in henry\n", "Vmax = 200;# in volts\n", "w = 500;# in rad/sec\n", "\n", "#calculation:\n", "Vrms = 0.707*Vmax\n", "f = w/(2*math.pi)\n", "XL = 2*math.pi*f*L\n", "Z = (R**2 + XL**2)**0.5\n", "I = Vrms/Z\n", "VL = I*XL\n", "VR = I*R\n", "phid = math.atan(XL/R)*180/math.pi\n", "\n", "\\\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)Impedance, Z = \",round(Z,2),\" ohms\"\n", "print \"\\n (b)current, I = \",round(I,2),\" A\"\n", "print \"\\n (c)p.d. across resistance, VR = \",round(VR,2),\" V\"\n", "print \"\\n (d)p.d. across Inductor, VL = \",round(VL,2),\" V\"\n", "print \"\\n (e)circuit phase angle is \",phid,\"deg\\n\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)Impedance, Z = 141.42 ohms\n", "\n", " (b)current, I = 1.0 A\n", "\n", " (c)p.d. across resistance, VR = 99.98 V\n", "\n", " (d)p.d. across Inductor, VL = 99.98 V\n", "\n", " (e)circuit phase angle is 45.0 deg" ] } ], "prompt_number": 2 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 11, page no. 218

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#determine the value of the supply voltage and the voltage across the 1.273 mH inductance.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "R = 30;# in ohms\n", "L = 1.2273E-3;# in henry\n", "f = 5000;# in Hz\n", "VR = 6;# in volts\n", "\n", "#calculation:\n", "I =VR/R\n", "XL = 2*math.pi*f*L\n", "Z = (R**2 + XL**2)**0.5\n", "V = I*Z\n", "VL = I*XL\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)supply voltage = \",round(V,2),\" Volts\"\n", "print \"\\n (b)p.d. across Inductor, VL = \",round(VL,2),\" V\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)supply voltage = 9.77 Volts\n", "\n", " (b)p.d. across Inductor, VL = 7.71 V" ] } ], "prompt_number": 11 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 12, page no. 219

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Determine (a) the impedance of the circuit, \n", "#(b) the current in the circuit, \n", "#(c) the circuit phase angle, \n", "#(d) the p.d. across the 60 ohm resistor\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "R = 60;# in ohms\n", "Rc = 20;# in ohms\n", "L = 159.2E-3;# in henry\n", "f = 50;# in Hz\n", "V = 240;# in volts\n", "\n", "#calculation:\n", "XL = 2*math.pi*f*L\n", "Rt = R + Rc\n", "Z = (Rt**2 + XL**2)**0.5\n", "I = V/Z\n", "phid = math.atan(XL/Rt)*180/math.pi\n", "VR = I*R\n", "Zc = (Rc**2 + XL**2)**0.5\n", "Vc = I*Zc\n", "VL = I*XL\n", "VRc = I*Rc\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)Impedance, Z = \",round(Z,2),\" ohms\"\n", "print \"\\n (b)current, I = \",round(I,3),\" A\"\n", "print \"\\n (c)circuit phase angle is \",round(phid,0),\"deg lagging\"\n", "print \"\\n (d)p.d. across resistance, VR = \",round( VR,1),\" V\"\n", "print \"\\n (e)p.d. across coil, Vc = \",round(Vc,1),\" V\"\n", "print \"\\n (f1)p.d. across Inductor, VL = \",round(VL,2),\" V\"\n", "print \"\\n (f2)p.d. across coil resistance, VRc = \",round(VRc,2),\" V\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)Impedance, Z = 94.35 ohms\n", "\n", " (b)current, I = 2.544 A\n", "\n", " (c)circuit phase angle is 32.0 deg lagging\n", "\n", " (d)p.d. across resistance, VR = 152.6 V\n", "\n", " (e)p.d. across coil, Vc = 137.0 V\n", "\n", " (f1)p.d. across Inductor, VL = 127.23 V\n", "\n", " (f2)p.d. across coil resistance, VRc = 50.88 V" ] } ], "prompt_number": 12 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 13, page no. 220

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate (a) the impedance, and (b) the current taken from a 240 V, 50 Hz supply. \n", "#Find also the phase angle between the supply voltage and the current.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "R = 25;# in ohms\n", "C = 45E-6;# in Farads\n", "f = 50;# in Hz\n", "V = 240;# in volts\n", "\n", "#calculation:\n", "Xc = 1/(2*math.pi*f*C)\n", "Z = (R**2 + Xc**2)**0.5\n", "I = V/Z\n", "phid = math.atan(Xc/R)*180/math.pi\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)Impedance, Z = \",round(Z,2),\" ohms\"\n", "print \"\\n (b)current, I = \",round(I,2),\" A\"\n", "print \"\\n (c)phase angle between the supply voltage and current is \",round(phid,2),\"deg leading\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)Impedance, Z = 75.02 ohms\n", "\n", " (b)current, I = 3.2 A\n", "\n", " (c)phase angle between the supply voltage and current is 70.54 deg leading" ] } ], "prompt_number": 1 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 14, page no. 221

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate: (a) the value of capacitance, C, \n", "#(b) the supply voltage, \n", "#(c) the phase angle between the supply voltage and current, \n", "#(d) the p.d. across the resistor, and\n", "#(e) the p.d. across the capacitor\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "R = 40;# in ohms\n", "f = 60;# in Hz\n", "I = 3;#in amperes\n", "Z = 50;# in ohms\n", "\n", "#calculation:\n", "Xc = (Z**2 - R**2)**0.5\n", "C = 1/(2*math.pi*f*Xc)\n", "V = I*Z\n", "phid = math.atan(Xc/R)*180/math.pi\n", "VR = I*R\n", "Vc = I*Xc\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)capacitance, C = \",round((C/1E-6),2),\" uF\"\n", "print \"\\n (b)Voltage, V = \",V,\" Volts\"\n", "print \"\\n (c)phase angle between the supply voltage and current is \",round(phid,2),\"deg leading\"\n", "print \"\\n (d)p.d. across resistance, VR = \", VR,\" V\"\n", "print \"\\n (e)p.d. across Capacitor, Vc = \",Vc,\" V\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)capacitance, C = 88.42 uF\n", "\n", " (b)Voltage, V = 150 Volts\n", "\n", " (c)phase angle between the supply voltage and current is 36.87 deg leading\n", "\n", " (d)p.d. across resistance, VR = 120 V\n", "\n", " (e)p.d. across Capacitor, Vc = 90.0 V" ] } ], "prompt_number": 2 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 15, page no. 222

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate (a) the current flowing, \n", "#(b) the phase difference between the supply voltage and current, \n", "#(c) the voltage across the coil and \n", "#(d) the voltage across the capacitor\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "R = 5;# in ohms\n", "C = 100E-6;# in Farads\n", "L = 0.12;# in Henry\n", "f = 50;# in Hz\n", "V = 300;# in volts\n", "\n", "#calculation:\n", "XL = 2*math.pi*f*L\n", "Xc = 1/(2*math.pi*f*C)\n", "X = XL - Xc\n", " #Since XL is greater than Xc, the circuit is inductive.\n", "Z = (R**2 + (XL-Xc)**2)**0.5\n", "I = V/Z\n", "phid = math.atan((XL-Xc)/R)*180/math.pi\n", "Zcl = (R**2 + XL**2)**0.5\n", "Vcl = I*Zcl\n", "phidc = math.atan(XL/R)*180/math.pi\n", "Vc = I*Xc\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)Current,I = \",round(I,2),\" A\"\n", "print \"\\n (b)phase angle between the supply voltage and current is \",round(phid,2),\"deg\"\n", "print \"\\n (c)Voltage across the coil, Vcoil = \",round(Vcl,0),\" Volts\"\n", "print \"\\n (d)p.d. across Capacitor, Vc = \",round(Vc,0),\" V\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)Current,I = 38.91 A\n", "\n", " (b)phase angle between the supply voltage and current is 49.57 deg\n", "\n", " (c)Voltage across the coil, Vcoil = 1480.0 Volts\n", "\n", " (d)p.d. across Capacitor, Vc = 1239.0 V" ] } ], "prompt_number": 13 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 16, page no. 224

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate (a) the circuit current, \n", "#(b) the circuit phase angle and \n", "#(c) the voltage drop across each impedance.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "R1 = 8;# in ohms\n", "C = 0.25E-6;# in Farads\n", "L = 130E-6;# in Henry\n", "Rc = 5;# in ohms\n", "R2 = 10;# in ohms\n", "f = 20000;# in Hz\n", "V = 40;# in volts\n", "\n", "#calculation:\n", "XL = 2*math.pi*f*L\n", "Xc = 1/(2*math.pi*f*C)\n", "X = Xc - XL\n", "R = R1 + R2 + Rc\n", " #Since Xc is greater than XL, the circuit is capacitive.\n", "Z = (R**2 + (Xc-XL)**2)**0.5\n", "I = V/Z\n", "phid = math.atan((Xc-XL)/R)*180/math.pi\n", "V1 = I*R1\n", "V2 = I*((Rc**2 + XL**2)**0.5)\n", "V3 = I*((R2**2 + Xc**2)**0.5)\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)Current,I = \",round(I,2),\" A\"\n", "print \"\\n (b)circuit phase angle is \",round(phid,2),\"deg leading\"\n", "print \"\\n (c1)Voltage across the Resistance of 8 ohms = \",round(V1,2),\" Volts\"\n", "print \"\\n (c2)Voltage across the coil, Vcoil = \",round(V2,2),\" Volts\"\n", "print \"\\n (c3)p.d. across Capacitor resistance circuit = \",round(V3,2),\" Volts\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)Current,I = 1.44 A\n", "\n", " (b)circuit phase angle is 33.97 deg leading\n", "\n", " (c1)Voltage across the Resistance of 8 ohms = 11.54 Volts\n", "\n", " (c2)Voltage across the coil, Vcoil = 24.64 Volts\n", "\n", " (c3)p.d. across Capacitor resistance circuit = 48.12 Volts" ] } ], "prompt_number": 3 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 17, page no. 224

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Determine the p.d.\u2019s V1 and V2 for the circuit\n", "#determine the supply voltage V and the circuit phase angle.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "R1 = 4;# in ohms\n", "C = 1.273E-6;# in Farads\n", "L = 0.286E-3;# in Henry\n", "R2 = 8;# in ohms\n", "f = 5000;# in Hz\n", "I = 5;# in amperes\n", "\n", "#calculation:\n", "XL = 2*math.pi*f*L\n", "phid1 = math.atan(XL/R1)*180/math.pi\n", "V1 = I*((R1**2 + XL**2)**0.5)\n", "Xc = 1/(2*math.pi*f*C)\n", "V2 = I*((R2**2 + Xc**2)**0.5)\n", "phid2 = math.atan(Xc/R2)*180/math.pi\n", "Z = ((R1+R2)**2 + (Xc-XL)**2)**0.5\n", "V = I*Z\n", "phid = math.atan((Xc-XL)/(R1+R2))*180/math.pi\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)Voltage supply, V = \",round(V,2),\" V\"\n", "print \"\\n (b)circuit phase angle is \",round(phid,2),\"deg leading\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)Voltage supply, V = 100.08 V\n", "\n", " (b)circuit phase angle is 53.16 deg leading" ] } ], "prompt_number": 5 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 18, page no. 226

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#At what frequency does resonance occur?\n", "#Find the current flowing at the resonant frequency.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "R = 10;# in ohms\n", "C = 60E-6;# in Farads\n", "L = 125E-3;# in Henry\n", "V = 120;# in Volts\n", "\n", "#calculation:\n", "fr = 1/(2*math.pi*(L*C)**0.5)\n", " #At resonance, XL = Xc and impedance Z = R\n", "I = V/R\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)Resonance frequency,Fr = \",round(fr,2),\" Hz\"\n", "print \"\\n (b)Current, I = \",round(I,2)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)Resonance frequency,Fr = 58.12 Hz\n", "\n", " (b)Current, I = 12.0" ] } ], "prompt_number": 18 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 19, page no. 226

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#find (a) the circuit resistance, and (b) the circuit capacitance.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "L = 0.05E-3;# in Henry\n", "fr = 200000;# in Hz\n", "V = 0.002;# in Volts\n", "I = 0.1E-3;# in amperes\n", "#calculation:\n", "# L-C-R\n", "#At resonance, XL = Xc and impedance Z = R\n", "R = V/I\n", "C = 1/(L*(2*math.pi*fr)**2)\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)Resistance, R = \",round(R,2),\" ohms\"\n", "print \"\\n (b)Capacitance, C = \",round((C/1E-9),2),\"nF\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)Resistance, R = 20.0 ohms\n", "\n", " (b)Capacitance, C = 12.67 nF" ] } ], "prompt_number": 19 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 20, page no. 227

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Determine (a) the resonant frequency, and \n", "#(b) the current at resonance. \n", "#How many times greater than the supply voltage is the voltage across the reactances at resonance?\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "L = 80E-3;# in Henry\n", "C = 0.25E-6;# in Farads\n", "R = 12.5;# in ohms\n", "V = 100;# in Volts\n", "\n", "#calculation:\n", "fr = 1/(2*math.pi*((L*C)**0.5))\n", " #At resonance, XL = Xc and impedance Z = R\n", "I = V/R\n", "VL = I*(2*math.pi*fr*L)\n", "Vc = I/(2*math.pi*fr*C)\n", "Vm = VL/V\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)the resonant frequency = \",round(fr,2),\" Hz\"\n", "print \"\\n (b)Current, I = \",round(I,2),\"\"\n", "print \"\\n (b)Voltage magnification at resonance = \",round(Vm,2),\" V\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)the resonant frequency = 1125.4 Hz\n", "\n", " (b)Current, I = 8.0 \n", "\n", " (b)Voltage magnification at resonance = 45.25 V" ] } ], "prompt_number": 20 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 21, page no. 228

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Determine the Qfactor of the circuit at resonance\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "L = 60E-3;# in Henry\n", "C = 30E-6;# in Farads\n", "R = 2;# in ohms\n", "\n", "#calculation:\n", "Q = ((L/C)**0.5)/R\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n At resonance, Q-factor = \",round(Q,2)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " At resonance, Q-factor = 22.36" ] } ], "prompt_number": 21 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 22, page no. 228

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Determine (a) the resonant frequency, \n", "#(b) the current at resonance,\n", "#(c) the voltages across the coil and the capacitor at resonance, and\n", "#(d) the Q-factor of the circuit.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "L = 100E-3;# in Henry\n", "C = 2E-6;# in Farads\n", "R = 10;# in ohms\n", "V = 50;# in Volts\n", "\n", "#calculation:\n", "fr = 1/(2*math.pi*((L*C)**0.5))\n", " #At resonance, XL = Xc and impedance Z = R\n", "I = V/R\n", "VL = I*(2*math.pi*fr*L)\n", "Vc = I/(2*math.pi*fr*C)\n", "Q = VL/V\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)the resonant frequency = \",round(fr,2),\" Hz\"\n", "print \"\\n (b)Current, I = \",round(I,2),\"\"\n", "print \"\\n (c)Voltage across coil at resonance is \",round(VL,2),\"V \"\n", "print \"and Voltage across capacitance at resonance is \",round( Vc,2),\"V\"\n", "print \"\\n (d)At resonance, Q-factor = \",round(Q,2)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)the resonant frequency = 355.88 Hz\n", "\n", " (b)Current, I = 5.0 \n", "\n", " (c)Voltage across coil at resonance is 1118.03 V and Voltage across capacitance at resonance is 1118.03 V\n", "\n", " (d)At resonance, Q-factor = 22.36" ] } ], "prompt_number": 22 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 23, page no. 230

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Determine the bandwidth of the filter.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "L = 20E-3;# in Henry\n", "R = 10;# in ohms\n", "fr = 5000;# in Hz\n", "\n", "#calculation:\n", "Qr = (2*math.pi*fr)*L/R\n", "bw = fr/Qr\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n Bandwidth, (f2-f1) = \",round(bw,2),\" Hz\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " Bandwidth, (f2-f1) = 79.58 Hz" ] } ], "prompt_number": 23 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 24, page no. 231

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Find the power dissipated in the resistor.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "R = 5000;# in ohms\n", "Imax = 0.250;# in Amperes\n", "\n", "#calculation:\n", "Irms = 0.707*Imax\n", "P = Irms*Irms*R\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n Power, P = \",round(P,2),\" Watts\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " Power, P = 156.2 Watts" ] } ], "prompt_number": 24 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 25, page no. 231

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate the power dissipated.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "R = 60;# in ohms\n", "L = 75E-3;# in Henry\n", "V = 110;# in Volts\n", "f = 60;# in Hz\n", "\n", "#calculation:\n", "XL = 2*math.pi*f*L\n", "Z = (R**2 + XL**2)**0.5\n", "I = V/Z\n", "P = I*I*R\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n Power, P = \",round(P,2),\" Watts\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " Power, P = 165.02 Watts" ] } ], "prompt_number": 25 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 26, page no. 232

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Find the value of the inductance.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "VI = 300;# in VA\n", "V = 150;# in Volts\n", "f = 50;# in Hz\n", "\n", "#calculation:\n", "I = VI/V\n", "XL = V/I\n", "L = XL/(2*math.pi*f)\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n Inductance = \",round(L,2),\" H\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " Inductance = 0.24 H" ] } ], "prompt_number": 26 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 27, page no. 232

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Determine the rated power output and the corresponding reactive power.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "VI = 200000;# in VA\n", "pf = 0.8;# power factor\n", "\n", "#calculation:\n", "P = VI*pf\n", "Q = VI*math.sin(math.acos(pf))\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n rated power output is \",round(P/1000,2),\"KW and the corresponding reactive power is \",round(Q/1000,2),\"kvar\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " rated power output is 160.0 KW and the corresponding reactive power is 120.0 kvar" ] } ], "prompt_number": 27 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 28, page no. 233

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Calculate (a) the resistance, \n", "#(b) the impedance, \n", "#(c) the reactance, \n", "#(d) the power factor, and \n", "#(e) the phase angle between voltage and current.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "V = 120;# in Volts\n", "f = 50;# in Hz\n", "P = 400;# in Watt\n", "I = 8;# in Amperes\n", "\n", "#calculation:\n", "R = P/(I*I)\n", "Z = V/I\n", "XL = (Z**2 - R**2)**0.5\n", "pf = P/(V*I)\n", "phi = math.acos(pf)*180/math.pi\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)resistance = \",round(R,2),\" ohm \"\n", "print \"\\n (b)Impedance Z = \",round(Z,2),\" Ohm \"\n", "print \"\\n (c)reactance = \",round(XL,2),\" ohm \"\n", "print \"\\n (d)Power factor = \",round(pf,2),\"\"\n", "print \"\\n (e)phase angle = \",round(phi,2),\"deg lagging\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)resistance = 6.25 ohm \n", "\n", " (b)Impedance Z = 15.0 Ohm \n", "\n", " (c)reactance = 13.64 ohm \n", "\n", " (d)Power factor = 0.42 \n", "\n", " (e)phase angle = 65.38 deg lagging" ] } ], "prompt_number": 15 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 29, page no. 233

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Find (a) the current flowing, (b) the phase angle,\n", "#(c) the resistance, (d) the impedance, and (e) the capacitance.\n", "from __future__ import division\n", "import math\n", "#initializing the variables:\n", "V = 100;# in Volts\n", "f = 60;# in Hz\n", "P = 100;# in Watt\n", "pf = 0.5;# power factor\n", "\n", "#calculation:\n", "I = P/(pf*V)\n", "phi = math.acos(pf)*180/math.pi\n", "R = P/(I*I)\n", "Z = V/I\n", "Xc = (Z**2 - R**2)**0.5\n", "C = 1/(2*math.pi*f*Xc)\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n (a)Current I = \",round(I,2),\" A \"\n", "print \"\\n (b)phase angle = \",round(phi,2),\"deg leading\"\n", "print \"\\n (c)resistance = \",round(R,2),\" ohm \"\n", "print \"\\n (d)Impedance Z = \",round(Z,2),\" Ohm \"\n", "print \"\\n (e)capacitance = \",round((C/1E-6),2),\"uF \"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " (a)Current I = 2.0 A \n", "\n", " (b)phase angle = 60.0 deg leading\n", "\n", " (c)resistance = 25.0 ohm \n", "\n", " (d)Impedance Z = 50.0 Ohm \n", "\n", " (e)capacitance = 61.26 uF " ] } ], "prompt_number": 6 } ], "metadata": {} } ] }