Lesson 15 Ohm’s Law 电子技术专业英语教程

2020/5/24,电子技术专业英语教程,1,Lesson15OhmsLaw电子技术专业英语教程冯新宇主编电子工业出版社,Unit6LinearCircuitAnalysis,2020/5/24,电子技术专业英语教程,2,Lesson15OhmsLaw,BackgroundsTexttourLanguageinuseVocabularyStructureReading/writingtechniques,2020/5/24,电子技术专业英语教程,3,TerminologycurrentdensityCoulombslawAmprescircuitallaw,Backgrounds,2020/5/24,电子技术专业英语教程,4,Terminology,2020/5/24,电子技术专业英语教程,5,Currentdensity,Currentdensityisameasureofthedensityofflowofaconservedcharge.Usuallythechargeistheelectriccharge,inwhichcasetheassociatedcurrentdensityistheelectriccurrentperunitareaofcrosssection,butthetermcurrentdensitycanalsobeappliedtootherconservedquantities.Itisdefinedasavectorwhosemagnitudeisthecurrentpercross-sectionalarea.InSIunits,theelectriccurrentdensityismeasuredinamperespersquaremetre.,2020/5/24,电子技术专业英语教程,6,Coulombslaw,Coulombslaw,sometimescalledtheCoulomblaw,isanequationdescribingtheelectrostaticforcebetweenelectriccharges.Itwasdevelopedinthe1780sbyFrenchphysicistCharlesAugustindeCoulombandwasessentialtothedevelopmentofthetheoryofelectromagnetism.,2020/5/24,电子技术专业英语教程,7,Amprescircuitallaw,Inclassicalelectromagnetism,Amprescircuitallaw,discoveredbyAndr-MarieAmprein1826,relatestheintegratedmagneticfieldaroundaclosedlooptotheelectriccurrentpassingthroughtheloop.,2020/5/24,电子技术专业英语教程,8,Amprescircuitallaw,Maxwellderiveditagainelectrodynamicallyinhis1861paperOnPhysicalLinesofForceanditisnowoneoftheMaxwellequations,whichformthebasisofclassicalelectromagnetism.,2020/5/24,电子技术专业英语教程,9,OutlineBriefintroduction(para.1)ThediscoveryofOhmslaw(para.2)TheequationofOhmslaw(para.3-9)Temperatureeffects(para.10)Applicationtocircuitanalysis(para.11-16)TransientsandACcircuits(para.17-23),Texttour,2020/5/24,电子技术专业英语教程,10,electriccurrentisproportionaltoapotentialdifferencefirstdiscoveredbyHenryCavendishOhmpublishedthelaw,ThediscoveryofOhmslaw,2020/5/24,电子技术专业英语教程,11,voltage,currentandresistanceareinterrelatedonamacroscopiclevelthemathematicalequationisPhysicistsoftenusethecontinuumformofOhmsLaw:,TheequationofOhmslaw,2020/5/24,电子技术专业英语教程,12,resistancewillusuallyincreaseastemperatureTheresistanceofanohmicsubstancedependsontemperatureinthefollowingway:exceptionissemiconductors,Temperatureeffects,2020/5/24,电子技术专业英语教程,13,Applicationtocircuitanalysis,ResistorsinseriesResistorsinparallel,2020/5/24,电子技术专业英语教程,14,Vocabularycontinuum，framework,terminalStructure,Languageinuse,2020/5/24,电子技术专业英语教程,15,Vocabulary,2020/5/24,电子技术专业英语教程,16,acontinuousseriesorwhole,nopartofwhichisperceptiblydifferentfromtheadjacentparts,continuumindictionary,2020/5/24,电子技术专业英语教程,17,continuumintext,PhysicistsoftenusethecontinuumformofOhmsLaw:whereJisthecurrentdensity(currentperunitarea,unlikethesimplerI,unitsofamperes,ofOhmslaw),istheconductivityandEistheelectricfield(unitsofvoltspermeter,unlikethesimplerV,unitsofvolts,ofOhmslaw).,2020/5/24,电子技术专业英语教程,18,continuumintext,物理学家通常使用欧姆定律的连续形式：，其中J是电流密度（即每单位面积上的电流，而不是欧姆定律中简单的I，单位是安培），是电导率，E是电场（单位为伏特/米，而不是欧姆定律中简单的V，单位为伏特）。,2020/5/24,电子技术专业英语教程,19,continuumstructure连续体结构continuumspectrum连续谱homogeneouscontinuum各向同性连续介质applicationcontinuum应用一体化continuumlimit连续极限equivalentcontinuum等效连续介质continuummodel连续介质模型,continuuminuse,2020/5/24,电子技术专业英语教程,20,astructuralplanorbasisofaprojectastructureorframesupportingorcontainingsomethingframescollectivelyworksuchasembroideryorweavingdoneinoronaframe,frameworkindictionary,2020/5/24,电子技术专业英语教程,21,AdetailedstudyoftheconceptualframeworkusedbyOhminformulatingOhmslawhasbeenpresentedbyArchibald.欧姆在欧姆定律中所构想的精确理论框架，最后由阿奇博尔德提出。,frameworkintext,2020/5/24,电子技术专业英语教程,22,cooperationframework合作范式macroscopicframework总体框架frameworktest框架测试budgetframework预算框架circuitframework电路结构frameworkfeature结构特征designingframework设计框架,frameworkinuse,2020/5/24,电子技术专业英语教程,23,adjof,being,orsituatedatanend,terminus,orboundaryof,relatingto,oroccurringafterorinaterm(ofadisease)terminatingindeathextremeoforrelatingtothestorageordeliveryoffreightatawarehouse,terminalindictionary,2020/5/24,电子技术专业英语教程,24,terminalindictionary,naterminatingpoint,part,orplaceapointatwhichcurrententersorleavesanelectricaldevice,suchasabatteryoracircuit.aconductorbywhichcurrententersorleavesatsuchapointadevicehavinginput/outputlinkswithacomputerbutsituatedatadistancefromthecomputer,2020/5/24,电子技术专业英语教程,25,terminalindictionary,anornamentalcarvingattheendofastructure.anothernamefortermapointorstationusuallyattheendofthelineofarailway,servingasanimportantaccesspointforpassengersorfreight.alesscommonnameforterminusapurpose-builtreceptionanddeparturestructureattheterminusofabus,sea,orairtransportroute,2020/5/24,电子技术专业英语教程,26,terminalindictionary,asitewhererawmaterialisunloaded,stored,insomecasesreprocessed,andreloadedforfurthertransportation,espanonshoreinstallationdesignedtoreceiveoffshoreoilorgasfromtankersorapipelinethesmallestarteriolebeforeitsdivisionintocapillaries.eitheroftwoveinsthatcollectbloodfromthethalamusandsurroundingstructuresandemptyitintotheinternalcerebralvein.theportionofabronchiolejustbeforeitsubdividesintotheairsacsofthelungs,2020/5/24,电子技术专业英语教程,27,ThetotalresistanceacrosstheterminalscanbecomputedbyaddingtheresistanceofR3totheequivalentresistanceoftheparallelcombinationR2/R1.如果电阻R3与R2/R1的并联组合相串联（通常用两条平等的杠“/”来表示并联），那么流过末端的总电阻可以通过以下方式估计，即将R3与R2/R1并联组合的等效电阻相加。,terminalintext,2020/5/24,电子技术专业英语教程,28,terminalutility最终效用terminalconstraint终端约束secondaryterminal次级线圈接线端,terminalinuse,2020/5/24,电子技术专业英语教程,29,Structure,2020/5/24,电子技术专业英语教程,30,Ohmslawisanextremelyusefulequationinthefieldofelectrical/electronicengineeringbecauseitdescribeshowvoltage,currentandresistanceare