自动化专业英语习题参考解答Unit1A.BasiclawsofElectricalNetworks[EX.1]Comprehension1.KCL:Thealgebraicsumofthecurrentsenteringanynodeiszero.KVL:Thealgebraicsumofthevoltagearoundanyclosedpathiszero.2.Node:Apointatwhichtwoormoreelementshaveacommonconnectioniscalledanode.Branches:asinglepathinanetworkcomposedofonesimpleelementandthenodeateachendofthatelement.Path:Ifnonodewasencounteredmorethanonce,thenthesetofnodesandelementsthatwehavepassedthroughisdefinedasapath.Loop:Ifthenodeatwhichwestartedisthesameasthenodeonwhichweended,thenthepathis,bydefinition,aclosedpathoraloop.apathisaparticularcollectionofbranches.3.4,5,Wecanformapathbutnotaloo.4.vR2=32V,Vx=6V[EX.2]TranslationfromEnglishtoChinese1.如果定义具有最大连接支路数的节点为参考节点，那么得到的方程相对来说比较简单。2.我们发现分析的主要步骤是得到含有一个未知变量的方程，该未知变量是该节点对两端的电压。3.然而，这个电阻相对于电路中其他的电阻来说是如此的小以至于我们可以在不引起明显误差的情况下忽略它的存在。4.与其他方式相比,下面这种方式在列方程时不容易犯错误.在头脑中按顺时针方向沿闭合路径走一遍,如果首先遇到的是元件标有号的端子,就直接写下它的电压;如果首先遇到的是标有的端子,则写下该电压的负值。5.正确分析电路的关键是先要在电路中规范地标出所有电压和电流。6.仔细写出KCL和KVL方程就可以得到正确的关系式，必要的时候，比如未知量多余最初得到的方程数时再应用欧姆定律。7.节点分析法基于基尔霍夫电流定律，运用节点分析法可以对不同的电路建立方程。8.注意，为了保持一致性，式中把所有的电流源（定义为流入节点1）放在了方程左边，把所有经过电阻流出节点1的电流放到了方程右边。9.在一个电路中，通过电阻的电压（称为压降），总有与电源极性相反的情况。10.因为电子流过一个电阻时会失去能量，因此它们会以较低的能级出现。[EX.3]TranslationfromChinesetoEnglish1.Itshouldbeemphasizedthatthevoltagecannotbedefinedinasinglepoint-itisdefinedasthepotentialdifferencebetweentwopoints.2.Notallofthegroundsaretheground;thisfactwillcausealotofsafetyissuesandelectricalnoise.3.Butasthesecorrosivepipesareplacedbylower-cost,moremodernandmorenon-conductivePVCpipingsystem,thelowimpedancepathtothegroundwillnotexistanymore.4.Kirchhoff'scurrentlawisbasedontheprincipleofconservationofcharge,andKirchhoff'svoltagelawisbasedonenergyconservationprinciple.Theyareboththebasiclawsofphysics.5.Ifthepublicportofthecircuitisnotconnectedwiththegroundthroughsomelow-impedancepath,itmayleadtosomepotentialdangers.6.Sincethesamecurrentflowsthrougheachresistor,thevoltagedropsareproportionaltotheOhmicvaluesoftheresistor.7.Ifallthevoltagedropsaroundaclosedloopareaddedandthenthistotalissubtractedfromthesourcevoltage,theresultiszero.8.Whentheresistorvoltagesareaddedtogether,theirsumwillequalthesourcevoltage.Anynumberofresistorscanbeadded.9.YoucanverifyKCLbyconnectingacircuitandmeasuringeachbranchcurrentandthetotalcurrentfromthesource.10.Additionalresistorsconnectedinparallelwillfurtherreducetheresistanceandincreasethetotalcurrent.[EX.4]Filloutthespaceaftertherecord.Inanodal1thevariablesinthecircuitareselectedtobethenodevoltage.Thenodevoltagesaredefinedwithrespecttoa2pointinthecircuit.Onenodeisselectedasthe3node,andallothernodevoltagesare4withrespecttothatnode.Quiteoftenthisnodeistheonetowhichthelargestnumberof5areconnected.Itiscommonlycalled6becauseitissaidtobeatground-zero7,anditsometimesrepresentsthechassisorgroundlineinan8circuit.Wewillselectourvariablesasbeing9withrespecttothereferencenode.Ifoneormoreofthenodevolt...
