{ "metadata": { "name": "", "signature": "sha256:3d029ef4e834a5cd003571095b5e7fdf64f109f6f6e91dbd7ffcf37b297f5b62" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 4: Work Power and Energy" ] }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 4.1: Page 61" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data :\n", "I=11;# current in A\n", "V1=55;# voltage in V\n", "V2=220;# voltage in V\n", "\n", "#calculations\n", "V=V2-V1;\n", "R=V/I; \n", "P=I**2*R;\n", "\n", "#Results\n", "print \"(a)resistance,R = \", R,\" ohm\" \n", "print \"(b)power lost,P = \",P,\" W\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "(a)resistance,R = 15.0 ohm\n", "(b)power lost,P = 1815.0 W\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 4.2: Page 61" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data :\n", "V=300;# voltage in volts\n", "W=360;# power lost in one coil in watt\n", "I=6; # current in A\n", "\n", "#calculations:\n", "R1=V/I;\n", "R=V**2/W;\n", "a=(1/R1)-(1/R);\n", "r2=1/a;\n", "\n", "#Results\n", "print \"resistance of 360W coil1,R= \",R,\"ohm and \\n resistance of second coil2,r2=\",r2,\"ohm\" " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "resistance of 360W coil1,R= 250.0 ohm and \n", " resistance of second coil2,r2= 62.5 ohm\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 4.3: Page 61" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data :\n", "W1=100# in watt\n", "E=110# in volts\n", "W2=60# in watt\n", "\n", "#calculations:\n", "I1=W1/E# current taken by 100 w lamp\n", "I2=W2/E# current taken by 60W lamp\n", "I=I1-I2;\n", "R=E/I;\n", "\n", "#Results\n", "print \"resistance,R =\", R,\" ohm\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "resistance,R = 302.5 ohm\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 4.4: Page 62" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data :\n", "w=100;# in watt\n", "V=220;# voltage in volts\n", "\n", "#calculations:\n", "R1=V**2/w;\n", "Rp=R1/2;# total resistance of the circuit\n", "Ip=V/Rp;\n", "Wp=Ip**2*Rp;\n", "R2=V**2/w;\n", "Rs=R1+R2;# total resistance of the circuit\n", "Is=V/Rs;\n", "Ws=Is**2*Rs;\n", "\n", "#Results\n", "print \"(a)power in case of parallel,W = \",Wp,\"watts\"\n", "print \"(b)power in case of series, W = \",Ws,\" Watts\" " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "(a)power in case of parallel,W = 200.0 watts\n", "(b)power in case of series, W = 50.0 Watts\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 4.5: Page 63" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data :\n", "V = 220; #voltage\n", "l=300;# number of lamps\n", "w1=60;# in watt\n", "w2=40;# in watt\n", "f=100;# number of fan\n", "\n", "# Calculations:\n", "W1=w1*l;# wattage required for 300 lamps, 60 watt each\n", "W2=w2*f# wattage required for 100 fans, 40 watt each\n", "W=(W1+W2)*10**-3;\n", "I=(W*1000)/V;\n", "\n", "#Results\n", "print \"(a)total load,W = \",W,\" kW\" \n", "print \"(b)current,I = \",I,\"A\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "(a)total load,W = 22.0 kW\n", "(b)current,I = 100.0 A\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 4.6: Page 63" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given and Calculations:\n", "nl=12#no. of lamps\n", "wl=100#wattage of lamps\n", "hl=6 #each lamps work 6 hours a days\n", "nf=6 #no. of fans\n", "wf=60#wattage of fans\n", "hf=5 #each fans work 5 hours a days\n", "nc=2 #no. of electric cookers\n", "wc=1500#wattage of electric cookers\n", "hc=4 #each electric cookers work 4 hours a days\n", "ng=2 #no. of gysers\n", "wg=1000#wattage of each gyser\n", "hg=3 #each gyser works 3 hours a day\n", "Ccg=40#IN PAISA\n", "Ccg1=35#IN PAISA\n", "\n", "# Calculations:\n", "w12=wl*nl*hl#wattage of 12 lamps in Wh\n", "w6=wf*nf*hf#wattage of 12 fans in Wh\n", "w2=wc*nc*hc#wattage of 2 electric cookers in Wh\n", "w21=wg*hg*ng#total wattage of gysers in Wh\n", "tcg=(w12+w6)*10**-3#TOTAL WATTAGE OF LAMPS AND FANS\n", "Ecg= (tcg*Ccg*30)/100#TOTAL ENERGY CHARGES @40 PAISA PER UNIT\n", "tcg1=(w2+w21)*10**-3#TOTAL WATTAGE OF COOKERS AND GYSERS\n", "Ecg1= (tcg1*Ccg1*30)/100#TOTAL ENERGY CHARGES @35 PAISA PER UNIT\n", "tc=Ecg+Ecg1# IN RUPPES\n", "\n", "#Results\n", "print \"total cost of electric charge @40 paisa per unit in rupees\",Ecg\n", "print \"total cost of electric charge @35 paisa per unit in rupees\",Ecg1\n", "print \"total charge for ligh and power in rupees\",tc" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "total cost of electric charge @40 paisa per unit in rupees 108.0\n", "total cost of electric charge @35 paisa per unit in rupees 189.0\n", "total charge for ligh and power in rupees 297.0\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 4.7: Page 63" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from __future__ import division\n", "import math\n", "\n", "#given and Calculations\n", "V = 250;#volts\n", "r = 0.03; #in ohms\n", "I = 20; #in Amps\n", "nl=400#no. of lamps\n", "wl=100#wattage of lamps\n", "nf=100#no. of fans\n", "wf=40#wattage of fans\n", "nc=200#no. of wall scokets\n", "wc=60#wattage of wall scckets\n", "hl=50#heating load in kW\n", "h=5 # hours\n", "\n", "# Calculations:\n", "w400=wl*nl#wattage of 400 lamps in W\n", "w6=wf*nf#wattage of 100 fans in W\n", "w2=wc*nc#wattage of 200 wall sockets in Wh\n", "tc= (w400+w6+w2)/1000#total consumption in kW\n", "Ml=V*I/1000#miscellaneous loads in kW\n", "Mo= ((50*80*746)/(100*1000))#MOTOR AT 80% LOAD IN Kw\n", "tl=tc+Ml+hl+Mo#total load in kW\n", "It = tl*1000/V\n", "Vc=It*r#voltage drop in the cable\n", "Vs=Vc+V#voltage at the sending end of the feeder in volts\n", "Pw=It**2*r#power wasted in kW\n", "ll=tc*h#lightning load in kWh\n", "te=Ml*2 + ll#TOTAL ENERGY COSNUMED PER DAY\n", "Nu=te*6#NO. OF UNITS\n", "Ec=(Nu*30)/100# ENERGY CHARGE @30 PAISA PER UNIT\n", "eCM=Ec+2+34.80#TOTAL CHARGE AFTER TAX AND RENT IN RUPEES.\n", "hlh=hl*4#heating load in kWh\n", "Moh=Mo*8#MOTOR LOAD IN kWh\n", "TEP=hlh+Moh#total energy per day\n", "tepl=TEP*6#total energy in 6 days\n", "tepc=(tepl*35)/100# energy charges @35 paisa per unit in rupees\n", "tepcl=tepc+50+78.96#total charges in rupess\n", "\n", "GTb = eCM + tepcl\n", "\n", "\n", "#Results\n", "print \"(a)total consumption of factory is \", tl,\"kW\"\n", "print \"(b)total current taken buy the factory\",It,\" Amp\"\n", "print \"(c)voltage at the sending end of the feeder is\",round(Vs,1),\"Volts\"\n", "print \"(d)power wasted is\",round(Pw/1000,2),\"kW\"\n", "print \"(e)total lightning charges- including meter rent and electricy tax is,(Rs)=\",round(eCM,2)\n", "print \"total power charges including meter rent and electricy tax is,(Rs)=\",round(tepcl,2)\n", "print \"grand total of bills is,(Rs)=\",round(GTb,2)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "(a)total consumption of factory is 140.84 kW\n", "(b)total current taken buy the factory 563.36 Amp\n", "(c)voltage at the sending end of the feeder is 266.9 Volts\n", "(d)power wasted is 9.52 kW\n", "(e)total lightning charges- including meter rent and electricy tax is,(Rs)= 558.8\n", "total power charges including meter rent and electricy tax is,(Rs)= 1050.27\n", "grand total of bills is,(Rs)= 1609.07\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 4.8: Page 64" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data :\n", "V=250;# voltage in volts\n", "L=5*746;# 1 hp=746 watt\n", "eta=80# eficiency of motor in %\n", "\n", "# Calculations:\n", "Input=(L*100)/80; \n", "I=Input/V;\n", "\n", "#Results\n", "print \"cureent,I(A) = \", I" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "cureent,I(A) = 18.65\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 4.9: Page 64" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given:\n", "p=30 #horse power of motor\n", "r=24 # rupees per kWh\n", "ec=35#paisa per unit\n", "n=80 #percentage of load\n", "t=8 # in hours\n", "d=25 # total days\n", "ne=96#efficiency of motor in percentage\n", "\n", "#calculations:\n", "mo=(n*p)/100#output of motor at 80% of load\n", "mi=(mo*100*746)/(ne)#input of motor in watts\n", "ecm=mi*10**-3*t*d#energy consumed in a month\n", "ecu=(ecm*35)/100#energy charges\n", "mid=(30*100*746)/(ne*1000)#input of motor in kW at demanded\n", "ecud=(mid*24)# demanded connection in rupees\n", "ta=ecu+ecud#total bill in rupees\n", "\n", "#Results\n", "print \"total bill in rupees is\",ta" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "total bill in rupees is 1865.0\n" ] } ], "prompt_number": 9 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 4.10: Page 65" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given:\n", "V=400#three phase voltage\n", "lp=50#no. of light points\n", "lw=60#wattage of light points\n", "fp=20#no. of fan points\n", "fw=100#wattage of fan points\n", "wpp=10#no. of wall plug points\n", "wppw=60#wattage of wall plug points\n", "bp=5 #no. of bell points\n", "bpw=40#wattage of bell points\n", "ppp=8#power plug points\n", "pppw=500#wattage of power plug points\n", "\n", "#calculations:\n", "lpw=lp*lw#wattage of 50 lamps\n", "fpw=fp*fw#wattage of 20 fans\n", "wpppw=wpp*wppw#wattage of wall plug points\n", "bpww=bp*bpw#wattage of bell points \n", "tl=lpw+fpw+wpppw+bpww#total wattage\n", "ppppw=ppp*pppw#wattage of power plug points\n", "tw=tl+ppppw#total wattage\n", "Il=(tl/V)# CURRENT THROUGH LIGHTNING LOAD\n", "Ip=ppppw/V# current through power load\n", "ttl=Il+Ip#total load curent\n", "\n", "#Results\n", "print \"total wattage of lightning load is in watts = \", tl\n", "print \"total load current in amperes = \",ttl" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "total wattage of lightning load is in watts = 5800\n", "total load current in amperes = 24.5\n" ] } ], "prompt_number": 10 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 4.11: Page 66" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data and calculations:\n", "h=30;# in m\n", "Fl=10# friction loss in %\n", "eta=90;# eficiency of pump\n", "w=1000;# water weight in kg\n", "flow_rate=243;# in per hour\n", "\n", "# Calculations:\n", "Hl=(Fl/100)*h;\n", "total_H=h+Hl;\n", "W_done=(flow_rate*w*total_H)/60;# in kg-m/min\n", "output=W_done/4500;#output of pump in hp\n", "In=(output*100)/eta;\n", "O=In;\n", "\n", "#Results\n", "print \"output of the motor,O(hp) = \",O" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "output of the motor,O(hp) = 33.0\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 4.12: Page 66" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "\n", "#given data:\n", "l=7.5#load in tonnes\n", "h=135#height in meters\n", "c=0.5#cge weight in tonnes\n", "b=3 #balance weight in tonnes\n", "td=90#time in seconds\n", "onet=1000# in kg\n", "onehp=746#watt\n", "\n", "#calculations:\n", "wl=l+c-b#weight lifted during upward journey in tonnes\n", "wld=b-c#weight lifted during downward journey in tonnes\n", "wdu=(wl*10**3*h*60)/td#work done by the lift per minute during upward journey\n", "wdd=(wld*10**3*h*60)/td#work done by the lift per minute during downward journey\n", "mou=wdu/4500# in hp\n", "miu=(mou*100*746)/(n*1000)# input of motor in kW\n", "mod=wdd/4500# in hp\n", "mid=(mod*100*746)/(n*1000)# input of motor in kW\n", "tc=miu+mid#total energy consumption in kW\n", "Eh=tc*10#total energy consuption per hour\n", "rate=40#rate in paisa\n", "ce=Eh*(rate/100)#cost of energy in rupees\n", "\n", "#Results\n", "print \"(a1)BHP of the motor in upward journey in hp\",mou \n", "print \"(a2)BHP of the motor in downward journey in hp\",mod\n", "print \"(b)cost of energy in rupees is\" ,ce" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "(a1)BHP of the motor in upward journey in hp 100.0\n", "(a2)BHP of the motor in downward journey in hp 50.0\n", "(b)cost of energy in rupees is 559.5\n" ] } ], "prompt_number": 12 } ], "metadata": {} } ] }