pec電子工程英語證書考試-電子學(xué)基本詞匯

1、PEC電子工程英語證書考試電子工程英語證書考試電子學(xué)基本詞匯電子學(xué)基本詞匯AALGITHMSAmathematicalequationthatproducesinafixednumberofstepstheanswertheanswertoaquestionthesolutiontoaproblem.ALTERNATINGCURRENTACVOLTAGEEithervoltagecurrentthatvariessmoothlyfrom

2、zerotoamaximumvalueinonedirectionpolarityreturnstozero.Itthenreversesitsdirection(polarity)risestoamaximumvalueintheoppositedirectionthenreturnstozerotocompletethecycle.Thiscycleisrepeatedcontinuously.Thenumberofcyclespe

3、rsecondisitsfrequencymeasuredinhertz(Hz).SeeSINEWAVE.ANALOGSIGNALAnelectricalsignalthathascontinuouslyvaryingvoltagesfrequenciesphases.AMPERETheunitofmeasurementofelectricalcurrentflownamedafterrAmprea19thcenturyFrenchph

4、ysicist.Oneampereisthevalueofcurrentthatwillbemaintainedinacircuitwithanelectromotivefceofonevoltaresistanceofoneohm.Oneampere=6.25x1018electronssecond.SeeCURRENT.AMPLIFICATIONTheprocessofincreasingthevoltagecurrentpower

5、ofanelectricalelectronicsignal.AMPLIFIERAnelectroniccircuitthatdrawspowerfromasupplyvoltagevoltagesourcetoproduceatitsoutputanincreasedreproductionofthesignalexistingatitsinput.Theamplifyingcomponentcouldbeatransistvacuu

6、mtubeanappropriatemagicdevice.ANALOGVOLTAGEAgraduallychangingvoltage.ThetermisinterchangeablewithLINEARVOLTAGE.Fexamplethevoltagesensedbyanautomobilesspeedometeristheanalogofthespeedoftheautomobile.NGSTROMUNITAunitofleng

7、ththatmeasureswavelengthisequalto0.1ofabillionthofameter(1x1010meters).Itisnamedafterersngstrma19thcenturySwedishphysicist.ARMATUREThemovingpartofamagicdeviceconsistingofonemecoilsthatareelectricallyconnectedtocreatether

8、otatablesectionofagenerat.SeeARMATUREinGlossaryofSwitchesKeyboardsElectromechanicalRelays.BBATTERYAnelectricaldeviceconsistingofonemecellswhichconvertschemicalsolarenergyintoelectricalenergy.Abatteryprovidesasourceofstea

9、dystateDCvoltage.BLOWTIMEThemaximumtimerequiredfafusetoopenafterbeingsubjectedtoanexcessofthedevicesratedcurrent.Fusesareclassifiedbyblowtimeasslownmalfast.CCELLAsingleunitofabatterythatgeneratesaDCvoltagebyconvertingche

10、micalsolarelectricalgeneratbattery.Whenconnectedtoaloadinaclosedcircuitthisfceproducesavoltageacrosstheloadcausescurrenttoflowinthatcircuit.EMFismeasuredinvoltsdesignatedwiththeletterE(supplyvoltage)V(loadvoltage).ELECTR

11、ONConsideredtobethesmallestunitofelectricalge.ELECTROSTATICGETheaccumulationofelectronsonthesurfaceofanonconductingmaterialwhenitisrubbedbyanothernonconductingmaterial.SeeTRIBOELECTRICEFFECT.ELECTROSTATICDISGE(ESD)Atrans

12、ferofanelectrostaticgebetweenamaterialwithanexcessofelectronsamaterialwithadeficiencyofelectrons.EXPONENTIALSYSTEMAconvenientmeansofnotatinglargesmallnumbersusingabasenumberasupere.g.102.FFREQUENCY(f)Thenumberofcyclesper

13、secondofanACwavemeasuredinhertz(Hz).FUNDAMENTALFREQUENCYThelowestfrequencyofacomplexACwaveshaperepresentedbyasinglesinewave.FUSEAshtstripofmetalhavingextremelylowresistancefunctioningasaprotectivedeviceinacircuit.Afusewi

14、llmeltwhenitsratedcurrentisexceededtherebyopeningthecircuit..GGROUNDThepartofacircuitsystemthatisthereferencefthevoltagesexistinginthatcircuitsystem.Thegroundconsistsofamaterialsuchascoppersteelaluminumanyotherconductive

15、material.SeeREFERENCE.HHARMONICSMultiplesofasinglesinewave(thefundamentalfrequency).Theevenharmonicsarethe2nd4th6thetc.theoddharmonicsarethe3rd5th7thetc.Allharmonicsaremultiplesoftheirfundamentalfrequency.HEATSINKAmetalb

16、aseplateontowhichonemecomponentsaremountedtoabsbcarryawayradiatetheheatgeneratedbythecomponent(s).Overheatingmayresultinthemalfunctiondestructionofthepart(s)generatingtheheatmightcausedamagetootherpartsofthecircuit.HERTZ

17、(HZ)TheunitofmeasurementofthefrequencyofasinewavesquarewavenamedafterHeinrichHertza19thcenturyGermanphysicist.Thetermhertzdesignatesthenumberofcyclespersecondexhibitedbythesewaves.HSEPOWER(HP)Aunitofmeasurementofmechanic