雨课堂学堂在线学堂云Electric Circuits(昆明理工大学)单元测试考核答案

第1题Theactualdirectionofcurrentisthedirectioninwhichthepositivechargemoves,whilethe____of

current

isarbitrarilyassumed.Whentheassumeddirectionisoppositetotheactualdirection,thecurrentvalueis____.正确答案：:referencedirection正确答案：:negative第2题The____ofvoltageisthedirection

fromthehighpotentialpointtothelowpotentialpoint,andthereferencedirectionofvoltageisartificiallyspecified.Thevoltagevalueispositivewhenthereferencedirectionis____theactualdirection.正确答案：:actualdirection正确答案：:thesameof第1题

Inthecircuitshowninfigure,IS＝10A

andUS＝12V,then(

).ABC第2题Whenthereferencedirectionsofvoltageandcurrentofabrancharethesame,

the

productof____isthepowerofthebranch____.正确答案：:voltageandcurrent正确答案：:absorbed1.4(2)Circuitelements第1题Inthecircuitshown,intermsofitsexternalcharacteristics,().AFigure2isequivalenttoFigure3.BFigure1isequivalenttoFigure4.CFigure1isequivalenttoFigure2.第2题Inthecircuitshowninthefigure,thepowerabsorbedbycontrolledsourceis().A2WB4WC6WD8W第3题Foranidealindependentcurrentsource,itsvoltageacross(

).Aonlydepends

onlyontheexternalcircuitandhasnothingtodowiththe

currentsourceBdepends

onthecurrentsourceitself

andhasnothingtodowiththe

externalcircuitCdepends

onthe

externalcircuitandcurrentsourceitselfDhas

nothingtodowiththatexternalcircuitandthecurrentsourceitself.第4题Thevolt-amperecharacteristiccurveofidealvoltagesourceisastraightlineparallelling

tothe____axis,andthevolt-amperecharacteristiccurveoftheidealcurrentsourceisastraightlineparallelling

tothe____axis.正确答案：:current正确答案：:voltage2.1第1题InthecircuitshowninFigure1-2,theportequivalentresistanceR=(

).A3ΩB8ΩC-2ΩD-5Ω第2题

InthecircuitshowninFigure1-2,theportequivalentresistanceR

=(

).A3ΩB5ΩC7ΩD9Ω2.2Nodes,Branches,andLoops第1题InthecircuitshowninFigure2-1,thecurrentsI1=____,I2=____,andthepowerfromthe4Vvoltagesource

P=____.正确答案：:1A正确答案：:3A正确答案：:-12W2.3第1题

Kirchhoff’sLawofVoltageandCurrentisrelatedto

circuit

().Anetworkstructure,notrelatedtocomponentpropertiesBnetworkstructureandcomponentpropertiesCcomponentsproperties,notrelatedtonetworkstructure第2题Inthecircuitshown,

I1

=().A0.5AB－1AC2AD1A第3题Forthe

circuitwithn

nodesandb

branches,

____independentKCLequationsand____KVLequations

canbelisted.正确答案：:n-1正确答案：:b-n+12.4第1题InthecircuitshowninFigure,

the

currentI1=____,I2=____,andthepowerfrom10Vvoltagesourceis____.正确答案：:4A正确答案：:2A正确答案：:80W2.5(1)第1题A15VB10C5VD0V第2题ABCD第3题Thecircuitisshowninthefigure.TheequivalentresistanceEQ1whenswitchSisopenedandclosedis().ABCD第4题InthecircuitshowninFigure,thevoltageu

=(

).A1VB2VC3VD4V2.6(1)第1题Theequivalentresistanceofthesingle-portnetworkshownbelowisequalto().ABCD第2题Theequivalentresistanceofthe

portnetworkshowninthefigureis().ABCD第3题AsshowninFigure,theinputresistanceofaportisequalto(

).A1.5ΩB2.5ΩC3.5ΩD4.5Ω第4题

Inthecircuitshowninfigure,theresistancevalueofeachresistoris1Ω,thenRab=(

).A3ΩB2ΩC1ΩD0.5Ω第5题AsshowninFigure,theequivalentcircuitofthesingle-portnetwork

is

(

).ABCD3.1第1题

Ifyouwanttoknowallbranchvoltagesofacircuitwithnnodesandbbranches,youneedtomeasureatleast().ABCD第2题Inthecircuitshowninthefigure,thehomingofnode①isequalto(

).ABCD第3题In

thecircuitshowninFigure,thecurrenti=(

).A2AB3AC4AD5A第4题

In

thecircuitshowninFigure,thenodevoltageequationof

nodecis(

).ABCD3.2第1题ABCD第2题InthecircuitshowninFigure,thenodevoltageu1=____,u2=____,u3=____,andbranchcurrent

i

=____.正确答案：:5V正确答案：:2V正确答案：:7V正确答案：:1.5A3.3第1题If

acircuitwithnnodesandbbranches,needtobedetermined

thecurrentofallbranches,itwillbemeasuredatleast(

).ABCD3.4第1题

InthecircuitshowninFigure,themeshcurrentsi1=____,i2=____,i3=____.正确答案：:1.6A正确答案：:0.8A正确答案：:1A4.1第1题InthecircuitshowninFigure,thecurrentI

=(

).A1AB2AC3AD4A4.2第1题InthecircuitshowninFigure,ifthesuperpositiontheoremisusedtocalculate

thecurrenti,thecurrentgeneratedbythe1Acurrentsourceactingalone

i′=____，andthecurrentgeneratedbythe1Vvoltagesourceactingalone

i″=____.正确答案：:1A正确答案：:1A第2题InthecircuitshowninFigure,whenthevoltageUab

iscalculatedby

thesuperpositiontheorem,theresponsesgeneratedby

5Vvoltagesourceand1Acurrentsourceare(

).A5V,8VB5V，-2VC0V,2VD0V,8V4.4第1题Inthecircuitshownbelow,theopencircuitvoltageUOC

=().A15vB18vC16v第2题InthecircuitshowninFigure,therelationshipoftheportu−iis(

)ABCD第3题InthecircuitshowninFigure,theopencircuitvoltageattheabterminal

Uab=().

A10VB5VC0D-5V4.5第1题

Forexternalcircuits,oneportcomposedofanindependentpowersupply,alinearresistorandacontrolledsourcecanbeequivalently

replacedbyaparallelconnectionof____andresistor.Theresistance

isequalto____afterallindependentpowersuppliesinoneportaresettozero正确答案：:currentsource正确答案：:inputresistance;equivalentresistance4.6第1题

InthecircuitshowninFigure,themaximumpowerof

theresistoris().A1WB2WC4WD0.5W5.2第1题Theinputresistance

Rabofthecircuitshown

inthefigure

is().AR1BR1+R2CR1+R2R3R2+R3DR1+R35.3第1题A0VB-10VC10VDnoneoftheabove第2题A25VB-25VC-30VD30V第3题A-1B1C2D3第4题A0BUsC−UsD

alloftheabove第5题AUsB−UsC0Dinfinit第6题A200ΩB500ΩC2kΩD5kΩ第7题A5Ω,4VB5Ω,-4VC10Ω,

-4VD10Ω,

4第8题A-2V,∞B2V,

∞C

2V,0ΩD-2V,0Ω6.1第1题Beforeandafterthecircuitchange,whenthecapacitorcurrentis____thecapacitor____willnotjumpatthemomentofthecircuitchange.正确答案：:finitevalue正确答案：:voltage第2题AB2AC1AD0第3题WhenthecircuitshowninFigureisstable,theenergystorageof1Fcapacitoris(

).A1JB2JC4JD8J6.2第1题ABCD6.3第1题Inastabledirectcurrentcircuit,inductanceisequivalentto____,andcapacitanceisequivalentto____.正确答案：:shortcircuit正确答案：:opencircuit第2题AB20VC10VD06.4第1题WhenthecircuitshowninFigureisstable,theenergystorageof1Hinductoris____,andthatof0.5Fcapacitoris____.正确答案：:2J正确答案：:4J7.1第1题Thethreecomponentsofthefirst-orderdynamiccircuitare____,____,andsteady-stateresponse.正确答案：:initialconditions正确答案：:timeconstant7.2第1题Whendynamiccircuitswitching,ifthecapacitorcurrentandinductorvoltagebeforeandafterswitchingarelimitedvalues,thenthereare()beforeandafterswitching.ABCD第2题ABCD第3题InthecircuitshowninFigure,thetimeconstant

τ=(

).A0.5sB1sC2sD4s第4题A0.5sB1sC2sD4s7.4第1题ABCD8.1第1题Thethreecomponents

ofsinusoidalquantityare____

angularfrequency(orfrequency)and____.正确答案：:amplitude;effectivevalue正确答案：:initialphaseangle8.2第1题A1AB2AC0.5AΩD0.866A8.3第1题ABCD第2题ABCD8.4第1题ACapacitiveBInductiveCResistiveD0value第2题A45°B90°C-90°D-45°8.5第1题A15VB7VC5VD3V第2题InRLCseriesresonantcircuit,theinductorvoltageis____timesasmuchastheportvoltage;theRMSvalueofthe

capacitorvoltageisequaltothat

oftheinductorvoltage,butthephaseis____.正确答案：:Q正确答案：:converse第3题A4AB8AC10AD16A8.6第1题InthecircuitshowninFigure

,whentheangularfrequencyofthesinusoidalsignaladdedtotheabterminalis(),theabterminalisequivalenttoashortcircuit.ABCD第2题ABCD第3题ABCD第4题AsensibilityBcapacitiveCresistivityDunsure第5题Alow-passfilteringcharacteristicsBhigh-passfilteringcharacteristicsCbandpassfiltercharacteristicsDbandstopfiltercharacteristics9.1第1题Inthesinusoidalsteady-statecircuit

showninFigure,thereading(effectivevalue)oftheammeterA1

shouldbe

____,andthereading(effectivevalue)oftheammeterA2

shouldbe____.正确答案：:5A正确答案：:3A9.2第1题ABCD第2题ABCD第3题ABCD第4题Inthesinusoidalsteady-statecircuitshowninFigure,

giventhat,us=102coswt(V).Inordertomaximizethermsvalueofcurrenti,theeffectivefrequency

ω

ofthepowersupplyshouldbe____.Atthistime,thermsvalueI

ofcurrenti

is____,andtheaveragepoweremittedbythepowersupplyis____.正确答案：:10rad/s正确答案：:5A正确答案：:50W第5题Inthesinusoidalsteady-statecircuitshowninFigure,

giventhat,

thentheRMSvalueofcurrentI1=____,theRMSvalueofcurrentI2=____,andtheaveragepowergeneratedbyth