Physical Modelling A學習通課后章節(jié)答案期末考試題庫2023年

PhysicalModellingA學習通課后章節(jié)答案期末考試題庫2023年Theconductioncurrentinacircuitisalwayscontinuous.

參考答案:

錯

AsmallblockofmassmisreleasedonatriangularblockofmassM.Ifatthesametime

aforceF=（m+M）gtanθ

isappliedtoM,mremainsrestrelativetoM.(Assumingallsurfacesarefrictionless)

參考答案:

√

Newton'slawscanbeusedinanyreferenceframe.

參考答案:

×

Apersonstandsonabathroomscaleinanelevator.Whenthescalereadsonly75%oftheperson’sregularweight,heclaimsthattheelevatormustbemovingdownward.Isheright?

參考答案:

×

Anobjectmovinginr=100mcirclesatisfies:howmuchisthemagnitudeofaccelerationwhent=1s?

參考答案:

15

Ifweknowtheaccelaration

ofanobject,thenitsvelocitycanbeexpressedas:

參考答案:

×

Iftheelectricfluxthroughaclosedsurfaceis0,thenthereisnonetchargeinsidethesurface.

參考答案:

對

Ablockofmassm=8.5kg,movingonasfrictionlesssurfacewithaspeed,makesaperfectlyelasticcollisionwithablockofmassMatrest.Afterthecollision,the8.5blockrecoilswithaspeed

.InFigurebelow,themassMisabout

kg(2significantnumbers)

參考答案:

9.89

AparticleissuspendedfromapostontopofacartbyalightstringasshowninFigure.Thecartandparticleareinitiallymovingtotherightatconstantspeedv,withthestringvertical.Thecartsuddenlycomestorestwhenitrunsintoandstickstoabumper.Whichofthefollowingstatementsistrueaboutthecollisionprocess?

參考答案:

Thelinearmomentumoftheparticleisconserved.

Ifthereisanelasticcollisionbetweentwoobjects,theirtotalkineticenergywillnotchange.

參考答案:

√

WaterisjettingatrateofR=1.5kg/swithv=20m/sonacar,andsplashesbackwithv'=10m/sintheoppositedirection.Whatistheforceexertedonthecar?F=_________N

參考答案:

45

Thetotalmomentumofasystem

remainsconstantinanycase.

參考答案:

×

Onlynonconservativeforcescanchangethekineticenergyofanobject.

參考答案:

×

Ifaparticlehasaconstantspeed,itsaccelerationequals0.

參考答案:

×

Inacircularmotion,theaccelerationisalwaysperpendiculartothevelocity.

參考答案:

×

Whichofthefollowingideasishelpfulinunderstandingprojectilemotion?

參考答案:

Thehorizontalmotionisindependentoftheverticalmotion.

HowdoesthecapacitancechangeifacapacitorCishalffilledwithdielectric(K=2)asshowninfigure?

參考答案:

1.5C

Aforceactingonanobjectdoesnoworkonit,iftheforceisalwaysperpendiculartothemovingdirectionofobject.

參考答案:

√

Thekineticenergyofanobjectdependsonthereferenceframeinwhichitsmotionismeasured.

參考答案:

√

AconductorsphericalshellcarrieschargeQ=3C,Anotherpointchargeq=2Cislocatedinsidetheshell.Howmuchistheelectricchargedistributedontheoutersurfaceoftheconductorshell?

參考答案:

5C

WecanconnecttwoinductorsL1andL2inseriestogetalargerinductor.ComparethetotalinductanceLwithL1+L2,whichstatementistrue?

參考答案:

Allthe3resultsarepossible

Whichofthefollowingfiguresaboutfieldlinecanrepresentanelectrostaticfieldinrealworld?

參考答案:

FigureC

Newton'ssecondlawsays:theaccelerationofanobjectisdirectlyproportionaltothenetforceactingonitandisinverselyproportionaltoits________.(oneword)

參考答案:

mass

UniformmagneticfieldincylindricalspacechangesasdB/dt=C>0.Ifastraightwireandacurvedwirearebothplacedinthechangingfieldasshowninthefigure,whichonehasagreaterEMFinit?

參考答案:

thecurvedwire

Whathappenswhenachargedinsulatorisplacednearanunchargedmetallicobject?

參考答案:

Theyattracteachother.

Therearesomestatementsabouttheelectromagneticwave.WhichofthemisNOTcorrect?

參考答案:

Theyrequireamediumthroughwhichtopropagate.

Ifthefollowingdevicesarealluniformlycharged,whichofthemcanproduceauniformelectricfield?

參考答案:

Solidspherewithasphericalholeinsideit;

FromUto_______×U

參考答案:

5

Whenwechoosetwodifferentreferenceframesto

analyzethemotionofanobject,thedescriptionofmotioncanbedifferent.

參考答案:

√

Thecapacitanceofacapacitorusuallydependsonitssize,shape,relativepositionoftwoconductors,andvoltagebetweentwoconductors.

參考答案:

錯

Theinductanceofanelectricdeviceisindependentoftheelectriccurrentitcarries.

參考答案:

對

AboutGauss'slaw,whichofthefollowingstatementsisTRUE?

參考答案:

Iftheelectricfieldinsidetheclosedsurfaceisuniform,thereisnochargeinsidetheclosedsurface;

Aconductorinelectrostaticfieldisanequipotentialbody,anytwopointsontheconductorhavethesameelectricpotential.

參考答案:

對

Ifseveralchargesarepresent,thenetforceonanyoneofthemwillbethealgebraicsumofforcesduetoeachoftheothers.

參考答案:

錯

AconductormovinginmagneticfieldcausesamotionalEMF,itcanbeexplainedbytheactionofLorentzforce.

參考答案:

對

Ifthreeunequalcapacitors,initiallyuncharged,areconnectedinseriesacrossabattery,whichofthefollowingstatementsisTRUE?

參考答案:

Thelargestvoltageappearsacrossthesmallestcapacitance;

A1500-kgcarmovingat20m/scrossestheroundedtopofahill(treatasanarcofcircle,radius100m).Whatisthenormalforce

N

actedbythehill?(g=9.80m/s^2)N

=_________N

參考答案:

8700

Ifaconductorisinanelectrostaticequilibrium,thentheelectricfieldinsideitatanypositionis0.

參考答案:

對

ε=_____V.

參考答案:

0.06

Thelinearintegralofelectrostaticfieldalongaclosedpathisdeterminedbythenetchargeinside.

參考答案:

錯

Ifthe

motionalequationofaparticleisexpressedaswhichofthefollowingstatementistrue?

參考答案:

Thespeedis

Gauss'slawisvalidonlywhenthechargedistributionishighlysymmetric.

參考答案:

錯

Someonemustgetdirectlyacrossa160mwideriver(fromAtoB).Theriver’scurrentis0.8m/s,hecanrowaboatat1.5m/s,andhecanrun3m/s.

Whatisthemaximumtimeforthecrossing?

t=________s

參考答案:

125

Microwaveovenuseselectromagneticwavetoheatfood.Supposethespaceinsidetheovencanbetreatedasfreespace.IftheelectricfieldatpointPintheovenismeasuredtobeE=6×106

V/m,thenthemagneticfieldatpointPatthesamemomentisB=_________T.

參考答案:

0.02

AcertainspringthatobeysHooke'slawisstretchedbyanexternalagent.Theworkdoneinstretchingthespringby10cmis4