电气专业英语试卷-复习A卷

第1页共4页电气专业英语试卷一.中英文单词互译.(1’*25=25’)1．inductor2．sensor3．manufacture4．insulator5．conductor6．Current7．normallyopen8．voltage9．shaft10．switch11.磁场12．频率13．发电机14．速度15．二极管16．万用表17．继电器18．电池19．加速度20．齿轮21．三极管22．硅23．电阻24．电容25．晶体二．根据英文词组，写出中文意义（2’*10=20’）ontheotherhandtakeadvantageofnegativechargeelectricfieldfreeelectroncurrentflowsinewaveseriescircuitparallelcircuitPNjunction三．英文翻译成中文(3’*10=30’)1.Pressstartpushbutton.Circuitiscompletedwhenthenormallyopenpushbutton(PB)ismomentarilyclosed.2.Currentflowsfromvoltagesource,throughnormallyclosedstopPB,throughstartPB,throughthecontactorcoil,totheothersideofthevoltagesource.第2页共4页3.Thisenergizesthecoilandcausesallcontactstoclose4.Contactsclose.MotorwillstartsinceACvoltageisappliedthroughthecontactsdirectlytothemotor.5.TheholdingcontactcausethecurrentpaththroughthecoiltobecompletedafterthestartPBisreleased.6.Motorwillrun.7.Pressstoppushbutton.8.ThecurrentpathisopenedbymomentarilyopeningthenormallyclosedstopPB.9.Thecoildeenergizes,causingthecontactstoopen.10.Motorwillstop.四．根据英文缩写，写出英文完整形式及中文意思（2’*5=10’）五.根据下列短文填空（1’*10=10’）Forcesbetweentwoelectrically-chargedobjectscanbeextremelylarge.Mostthingsareelectricallyneutral;theyhaveequalamountsofpositiveandnegativecharge.Ifthiswasn’tthecase,theworldweliveinwouldbeamuchstrangerplace.Wealsohavealotofcontroloverhowthingsgetcharged.Thisisbecausewecanchoosetheappropriatematerialtouseinagivensituation.Metalsaregoodconductorsofelectriccharge,whileplastics,wood,andrubbersarenot.Theyarecalledinsulators.Chargedoesnotflownearlyaseasilythroughinsulatorsasitdoesthroughconductors,whichiswhywiresyouplugintoawallsocketarecoveredwithaprotectiverubbercoating.Chargeflowsalongthewire,butnotthroughthecoatingtoyou.Materialsaredividedintothreecategories,dependingonhoweasilytheywillallowcharge(i.e.,electrons)toflowalongthem.Theseare:英文完整形式中文意思PLCACCNCDCFMS第3页共4页conductors-metals,forexamplesemi-conductors-siliconisagoodexampleinsulators-rubber,wood,plasticforexampleMostmaterialsareeitherconductorsorinsulators.Thedifferencebetweenthemisthatinconductors,themostouterelectronsintheatomsaresolooselyboundtotheiratomsthattheyarefreetotravelaround.Ininsulators,ontheotherhand,theelectronsaremuchmoretightlyboundtotheatoms,andarenotfreetoflow.Semi-conductorsareaveryusefulintermediateclass,notasconductiveasmetalsbutconsiderablymoreconductivethaninsulators.Byaddingcertainimpuritiestosemi-conductorsintheappropriateconcentrationstheconductivitycanbewell-controlled.1.________aregoodconductorsofelectriccharge,whileplastics,wood,and_________arenot.2.Materialsaredividedintothreecategories.Theyare________,_______and_________.3.Plastics,wood,andrubbersareusedasexamplesof________.4.________isagoodexampleofsemi-conductors.5.Semi-conductorsareaveryuseful______________class,notas___________asmetalsbutconsiderably___________conductivethaninsulators.六．根据下列短文回答问题,回答请使用英文。（1’*5=5’）ElectricPotentialElectricpotentialiswhatdrivescurrent.Youmayknowelectricpotentialbyanothertermthatwewilluse...voltage.Thisnamecomesfromtheunitofpotential,whichisthevolt(denotedV).WhenyoubuyanAAbattery,youarebuyingadevicethatprovidesapotentialof1.5Vbetweenitspositiveandnegativeterminals.Yourcarbatterymaintainsabout12Vbetweenitsterminals.Andthepotentialbetweenthetwoslotsinahouseholdelectricaloutletisabout120V.Youareprobablyalreadyfamiliarwithabasictruthaboutelectricpotential.Allotherthingsbeingequal,agreaterpotentialwillcreateagreatercurrent.Butwhatiselectricpotential?Watercanprovideagoodanalogy(althoughfarfromperfect!)forbothcurrentandpotential.Considerapipethatcomesoutofthebottomofalargetankofwater.Youopenthespigotandwaterflows.Theflowrateofthewaterisanalogoustocurrent.Commonsensetellsyouthatthehigherthewaterlevelinthetank,thehighertheflowrateinthepipe.Theheightofthewaterlevelisanalagoustoelectricpotential.Agreaterpotentialwillcauseagreatercurrent.Wherethisanalogyfailsiswiththebattery.Thetankstoreswaterandastheheightslowlydecreases,sodoesthewaterflow.Abatterydoesnotstorecharge!Itisalwayselectricallyneutralandforwhateveramountofchargeleavesoneterminal,anequalamountmustcomeintotheother.Abatteryismoreanalogoustothewaterpump.A第4页共4页battery,therefore,isanelectronpump!Ithastheabilitytopushelectronsdirectlyproportionaltoitsvoltagerating.And,itdoesthisthroughachemicalreaction.Thebatterybecomesdischarged,(anunfortunatelymisleadingterm),whenthechemicalsinthebatteryareusedup.Mostbatteriesmaintainafixedpotentialuntilneartheendoftheirlife.The120Vpotentialofahouseholdoutletisproducedinaverydifferentway.1.Whatisanalagoustoelectricpotential?2.Whatismoreanalogoustothewaterpump?3.Whatisabattery?4.Whatcanabatterydo?Andhow?5.Whatdomostbatteriesmaintainuntilneartheendoftheirlife?