{ "metadata": { "name": "", "signature": "sha256:e41e7a899079e095312b80bb51a6a04abde629cd10b5f06d1688520f00c1a4b7" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 11: Single Phase A-C Circuits" ] }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 11.1: page 211:" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data :\n", "E_max=500;# emf in volts\n", "thita=30;# in degree\n", "\n", "#calculations:\n", "e=E_max*math.sin(thita*math.pi/180);\n", "\n", "#Results\n", "print \"instantaneous value,e(v) = \",e " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "instantaneous value,e(v) = 250.0\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 11.2: page 212:" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data :\n", "I_max=1.414;# maximum value of current in A\n", "\n", "#calculations:\n", "I_rms=I_max*0.707;\n", "\n", "#Results\n", "print \"rms value of current,I_rms(A) = \",round(I_rms)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "rms value of current,I_rms(A) = 1.0\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 11.3: page 220:" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data :\n", "f=50;# frequency in Hz\n", "L=0.2;# inductance in H\n", "V=220;# voltage in volts\n", "\n", "#calculations:\n", "XL=2*math.pi*f*L# in ohm\n", "Z=XL;\n", "I=V/Z;\n", "\n", "#Results\n", "print \"current drawn,I(A) = \",round(I,2)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "current drawn,I(A) = 3.5\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 11.4: page 222:" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data :\n", "f=50;# frequency in Hz\n", "C=100*10**-6# capacitor in Farad\n", "V=210;# voltage in volts\n", "\n", "#calculations:\n", "XC=(1/(2*math.pi*f*C));\n", "Z=XC;\n", "I=V/Z;\n", "\n", "#Results\n", "print \"current flowing,I(A) = \",round(I,2)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "current flowing,I(A) = 6.6\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 11.5: page 222:" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data :\n", "f=50;# frequency in Hz\n", "L=0.4;# inductance in H\n", "V=220;# voltage in volts\n", "f1=25;# frequency is halved\n", "f2=100;# frequency is doubled\n", "\n", "#calculations:\n", "XL=2*math.pi*f*L;\n", "I=V/XL;\n", "\n", "XL1=2*math.pi*f1*L;\n", "I1=V/XL1;\n", "\n", "XL2=2*math.pi*f2*L;\n", "I2=V/XL2;\n", "\n", "#Results\n", "print \"current flowing,I(A) = \",round(I,2) \n", "print \"(a)current when frequency is halved,I(A) = \",round(I1,2)\n", "print \"current when frequency is doubled,I(A) = \",round(I2,3)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "current flowing,I(A) = 1.75\n", "(a)current when frequency is halved,I(A) = 3.5\n", "current when frequency is doubled,I(A) = 0.875\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 11.6: page 223:" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data :\n", "f=50;# frequency in Hz\n", "C=28*10**-6# capacitor in Farad\n", "V=250;# voltage in volts\n", "f1=25# when frequency is halved\n", "f2=100# when frequency is doubled\n", "\n", "#calculations:\n", "XC=1/(2*math.pi*f*C);\n", "I=V/XC;\n", "\n", "XC1=1/(2*math.pi*f1*C);\n", "I1=V/XC1;\n", "\n", "XC2=1/(2*math.pi*f2*C);\n", "I2=V/XC2;\n", "\n", "#Results\n", "print \"current flowing,I(A) = \",round(I,1)\n", "print \"current flowing when frequency is halved,I(A) = \",round(I1,1)\n", "print \"current flowing when frequency is doubled ,I(A) =\",round(I2,1)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "current flowing,I(A) = 2.2\n", "current flowing when frequency is halved,I(A) = 1.1\n", "current flowing when frequency is doubled ,I(A) = 4.4\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 11.7: Page 224:" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data:\n", "R=40 #in ohms\n", "L=0.07#IN HENRY\n", "V=223#IN VOLTS\n", "F=50 # IN HERTS\n", "\n", "#calculations:\n", "Xl=2*math.pi*F*L# inductive reactance in ohms\n", "Z=(R**2+Xl**2)**0.5#IMPEDENCE IN OHMS\n", "I=V/Z;#in amperes\n", "csp=R/Z#pf\n", "phi=math.acos(csp)#angle of phase differnce in degree\n", "\n", "def decdeg2dms(dd):\n", " mnt,sec = divmod(dd*3600,60)\n", " deg,mnt = divmod(mnt,60)\n", " return deg,mnt,sec\n", "phiAct = decdeg2dms(phi*180/math.pi)\n", "\n", "#Results\n", "print \"inductive reactance in ohms is\",round(Xl)\n", "print \"impedence in ohms is\",round(Z,2) \n", "print \"current in amperes is\",round(I,1)\n", "print \"angle of phase difference is \",phiAct[0],\"Degrees and \",phiAct[1],\"minutes\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "inductive reactance in ohms is 22.0\n", "impedence in ohms is 45.65\n", "current in amperes is 4.9\n", "angle of phase difference is 28.0 Degrees and 48.0 minutes\n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 11.8: Page 226:" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data:\n", "V=200#in volts\n", "I=2.5# in amperes\n", "Vo=250# in volts\n", "f=50 # in hertz\n", "\n", "#calculations:\n", "R=V/I# in ohms\n", "Z=Vo/I# in ohms\n", "Xl=(Z**2-R**2)**0.5#inductive reactance in ohms\n", "L=(Xl/(2*math.pi*f))#inductance in henry\n", "pf=R/Z#power factor\n", "phi=math.acos(pf)#angle of phase differnce in degree\n", "def decdeg2dms(dd):\n", " mnt,sec = divmod(dd*3600,60)\n", " deg,mnt = divmod(mnt,60)\n", " return deg,mnt,sec\n", "phiAct = decdeg2dms(phi*180/math.pi)\n", "\n", "#Results\n", "print \"inductance in henry is\",round(L,4)\n", "print \"angle of phase difference is \",phiAct[0],\"Degrees and \",phiAct[1],\"minutes\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "inductance in henry is 0.191\n", "angle of phase difference is 36.0 Degrees and 52.0 minutes\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 11.9: page 226:" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data:\n", "W=100#in watts\n", "V=110#in volts\n", "Vc=220#in volts\n", "f=50 #in hertz\n", "\n", "#calculations:\n", "I=W/V# in amperes\n", "R=V/I#in ohms\n", "Z=Vc/I# in ohms\n", "Xc=math.sqrt(Z**2-R**2)# IN OHMS\n", "C=(1/(2*math.pi*f*Xc))# in farads\n", "\n", "#Results\n", "print \"capacitance in micro farads is\",round(C*10**6,2)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "capacitance in micro farads is 15.19\n" ] } ], "prompt_number": 9 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 11.10: page 227:" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data:\n", "R=5.94#in ohms\n", "L=0.35#IN HENRY\n", "C=35 # in micro farads\n", "V=220#IN VOLTS\n", "F=50 # IN HERTS\n", "\n", "#calculations:\n", "Xc=(1/(2*math.pi*F*C*10**-6))# capacitive reactance in ohms\n", "Xl=2*math.pi*F*L# inductive reactance in ohms\n", "Z=math.sqrt(R**2+(Xl-Xc)**2)# impedence in ohms\n", "I=V/round(Z)# in amperes\n", "pf=R/round(Z)# power factor\n", "Zc=math.sqrt(R**2+Xl**2)#impedence of the coil\n", "Vl=I*Zc#voltage drop across the coil\n", "Vc=I*Xc#voltage drop across the capacitor\n", "W=I**2*R#total power taken in watts\n", "\n", "#Results\n", "print \"(a)impedence in ohms is\",round(Z)\n", "print \"(b)current in amperes is\",I\n", "print \"(c)angle of phase diffence between voltage and current is\",pf\n", "print \"(d)voltage across the coil in volts is\",round(Vl,1)\n", "print \"(e)voltage across capacitor in volts is\",round(Vc,1)\n", "print \"(f)total power taken in watts is\",round(W,1)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "(a)impedence in ohms is 20.0\n", "(b)current in amperes is 11.0\n", "(c)angle of phase diffence between voltage and current is 0.297\n", "(d)voltage across the coil in volts is 1211.3\n", "(e)voltage across capacitor in volts is 1000.4\n", "(f)total power taken in watts is 718.7\n" ] } ], "prompt_number": 10 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 11.11: page 233:" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data:\n", "r1=6 #in ohms\n", "r2=3.95#in ohms\n", "R=r1+r2#in ohms\n", "L1=0.21#IN HENRY\n", "L2=0.14#in henry\n", "C1=30# in micro farads\n", "C2=60#in micro farads\n", "V=220#IN VOLTS\n", "F=50 # IN HERTS\n", "\n", "#calculations:\n", "Xc1=(1/(2*math.pi*F*C1*10**-6))# capacitive reactance in ohms\n", "Xc2=(1/(2*math.pi*F*C2*10**-6))# capacitive reactance in ohms\n", "Xc=Xc1+Xc2#IN OHMS\n", "Xl1=2*math.pi*F*L1# inductive reactance in ohms\n", "Xl2=2*math.pi*F*L2# inductive reactance in ohms\n", "Xl=Xl1+Xl2#in ohms\n", "Z=math.sqrt(R**2+(Xl-Xc)**2)# impedence in ohms\n", "I=V/Z#\n", "pf=R/Z# leading power factor\n", "\n", "#Results\n", "print \"(a)impedence in ohms is\",round(Z)\n", "print \"(b)current in amperes is\",round(I)\n", "print \"(c)power factor (leading) is\",round(pf,3)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "(a)impedence in ohms is 50.0\n", "(b)current in amperes is 4.0\n", "(c)power factor (leading) is 0.198\n" ] } ], "prompt_number": 11 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 11.12: Page 233:" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data:\n", "V=200# in volts\n", "L=0.04# in henry\n", "C=100#in micro fards\n", "f=50 # hertz\n", "Z1=10#ohms\n", "R1=10# in ohms\n", "X1=0 # in ohms\n", "R2=5 # in ohms\n", "R3=15# in ohms\n", "\n", "#calculations:\n", "Xl=2*math.pi*f*L#inductive reactance in ohms\n", "Xc=(1/(2*math.pi*f*C*10**-6))#CAPACITIVE REACTANCE IN OHMS\n", "Z2=math.sqrt(R2**2+Xl**2)#in ohms\n", "X2=Xl#\n", "Z3=math.sqrt(R3**2+Xc**2)# IN OHMS\n", "X3=Xc#\n", "g1=R1/(Z1)**2# conductance of branch 1 in mho\n", "b1=X1/(Z1)**2#susceptance in mho in branch 1\n", "g2=R2/(Z2)**2# conductance of branch 2 in mho\n", "b2=X2/(Z2)**2#susceptance in mho in branch 2\n", "g3=R3/(Z3)**2# conductance of branch 3 in mho\n", "b3=X3/(Z3)**2#susceptance in mho in branch 3\n", "G=g1+g2+g3# total conductance in mho\n", "B=b1+b2-b3# total susceptance in mho\n", "Y=math.sqrt(G**2+B**2)#in ohms\n", "I0=V*Y#curent in ampere\n", "theta=math.acos(G/Y)#\n", "\n", "def decdeg2dms(dd):\n", " mnt,sec = divmod(dd*3600,60)\n", " deg,mnt = divmod(mnt,60)\n", " return deg,mnt,sec\n", "phiAct = decdeg2dms(theta*180/math.pi)\n", "\n", "I=V/Z3#curent in amperes\n", "pf3=R3/Z3#power factor\n", "phi=math.acos(pf3)#angle of phase differnce in degree\n", "\n", "\n", "tc3=pf3#\n", "ts3=math.sin(phi)\n", "pf1=R1/R1#\n", "tc1=pf1#\n", "ts1=math.sin(math.acos(pf1))#\n", "I1=V/Z1#\n", "E1=I1*tc1# energy component in branch 1\n", "EL1=I1*ts1# idel current component in branch 1\n", "I2=V/Z2#\n", "pf2=R2/Z2#\n", "tc2=pf2#\n", "ts2=math.sin(math.acos(pf2))#\n", "E2=I2*tc2#ENERGY COMPONENT IN BRANCH2\n", "EL2=I2*ts2#idele current component in branch 2\n", "E3=I*tc3#energy component in branch3\n", "EL3=I*ts3#idle component of current in branch 3\n", "E=E1+E2+E3#sum of energy component of current\n", "EL=EL1+EL2-EL3#sum of idel component of current\n", "It=math.sqrt(E**2+EL**2)# total current\n", "pft=E/It#power factor of the complete circuit\n", "phi=math.acos(0.95)#angle of phase differnce in degree\n", "\n", "Zt=V/It#in ohms\n", "R=Zt*pft#equivalent series resistance\n", "X=Zt*(math.sin(phi))#equivalent series reactance\n", "\n", "\n", "#Results\n", "print \"(a)current in amperes is\",round(I0)\n", "print \"Phase angle is \",phiAct[0],\"Degrees and \",phiAct[1],\"minutes\"\n", "print \"(c)equivalent series resistance in ohms is\",round(R,2)\n", "print \"euivalent series reactance in ohms is\",round(X,3)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "(a)current in amperes is 29.0\n", "Phase angle is 17.0 Degrees and 8.0 minutes\n", "(c)equivalent series resistance in ohms is 6.55\n", "euivalent series reactance in ohms is 2.14\n" ] } ], "prompt_number": 12 } ], "metadata": {} } ] }