大学物理双语-练习题

Chapter1ParticleKinematicsI)Chooseonecorrectansweramongfollowingchoices1.Anobjectismovingalongthex-axiswithpositionasafunctionoftimegivenbyx=x(t).PointOisatx=0.TheobjectisdefinitelymovingtowardOwhenA.B.C.D.2.Anobjectstartsfromrestatx=0whent=0.Theobjectmovesinthexdirectionwithpositivevelocityaftert=0.TheinstantaneousvelocityandaveragevelocityarerelatedbyA.B.C.D.canbelargerthan,smallerthan,orequalto3.Anobjectismovinginthexdirectionwithvelocity,andisnonzeroconstant.Withwhent=0,thenfort>0thequantityisA.Negative.B.Zero.C.Positive.D.Notdeterminedfromtheinformationgiven.4.Anobjectismovingonthexy-planewithpositionasafunctionoftimegivenbyr=at2i+bt2j(aandbareconstant).Whichiscorrect?A.Theobjectismovingalongastraightlinewithconstantspeed.B.Theobjectismovingalongastraightlinewithvariablespeed.C.Theobjectismovingalongacurvedpathwithconstantspeed.D.Theobjectismovingalongacurvedpathwithvariablespeed.5.Anobjectisthrownintotheairwithaninitialvelocitym/s.Ignoretheairresistance(空气阻力).Atthehighestpointthemagnitudeofthevelocityis()(A)0(B)4.9m/s(C)9.8m/s(D)m/s6.Twobodiesarefallingwithnegligibleairresistance,sidebyside,aboveahorizontalplane.Ifoneofthebodiesisgivenanadditionalhorizontalaccelerationduringitsdescent,itA.strikestheplaneatthesametimeastheotherbody.B.strikestheplaneearlierthantheotherbody.C.hastheverticalcomponentofitsvelocityaltered.D.hastheverticalcomponentofitsaccelerationaltered.7.Atoyracingcarmoveswithconstantspeedaroundthecircleshownbelow.WhenitisatpointAitscoordinatesarex=0,y=3manditsvelocityis6m/s.WhenitisatpointBitsvelocityandaccelerationare:A.-6m/sand12m/s2,respectively.B.6m/sand-12m/s2,respectively.C.6m/sand12m/s2,respectively.D.6m/sand2m/s2,respectively.8.Astoneistiedtoa0.50-mstringandwhirledataconstantspeedof4.0m/sinaverticalcircle.Itsaccelerationatthebottomofthecircleis:A.9.8m/s2,upB.9.8m/s2,downC.8.0m/s2,upD.32m/s9.Aboatisabletomovethroughstillwaterat20m/s.Itmakesaroundtriptoatown3.0kmupstream.Iftheriverflowsat5m/s,thetimerequiredforthisroundtripis:A.120sB.150sC.200sD.320sII)Fillintheemptyspacewithcorrectanswer1.Aparticlegoesfromx=-2m,y=3m,z=1mtox=3m,y=-1m,z=4m.Itsdisplacementis:.2.Thex-componentofthepositionvectorofaparticleisshowninthegraphinFigureasafunctionoftime.(a)Thevelocitycomponentvxattheinstant3.0sis.(b)Whenisthevelocitycomponentzero?Thetimeis.(c)Istheparticlealwaysmovinginthesamedirectionalongthex-axis?.3.Theangleturnedthroughbyawheelisgivenbyθ＝at+bt2,whereaandbareconstants.Itsangularvelocityω＝,anditsangularaccelerationβ＝.4.Whenaradiowaveimpingesontheantennaofyourcar,electronsintheantennamovebackandforthalongtheantennawithavelocitycomponentvxasshownschematicallyinFigure.Roughlysketchthesamegraphandindicatethetimeinstantswhen(a)Thevelocitycomponentvxiszero;(b)Theaccelerationcomponentaxiszero;(c)Theaccelerationhasitsmaximummagnitude.5.Acaristravelingaroundabanked,circularcurveofradius150monatesttrack.Attheinstantwhent=0s,thecarismovingnorth,anditsspeedis30.0m/sbutdecreasinguniformly,sothatafter5.0sitsangularspeedwillbe3/4thatitwaswhent=0s.Theangularspeedofthecarwhent=0sis,theangularspeed5.0slateris,themagnitudeofthecentripetalaccelerationofthecarwhent=0sis,themagnitudeofthecentripetalaccelerationofthecarwhent=5.00sis,themagnitudeoftheangularaccelerationis,themagnitudeofChapter3Linearmomentum,ConservationofmomentumI)Chooseonecorrectansweramongfollowingchoices1.Anobjectismovinginacircleatconstantspeedv.ThemagnitudeoftherateofchangeofmomentumoftheobjectA.iszero.B.isproportionaltov.C.isproportionaltov2.D.isproportionaltov3.2.Ifthenetforceactingonabodyisconstant,whatcanweconcludeaboutitsmomentum?A.Themagnitudeand/orthedirectionofmaychange.B.Themagnitudeofrremainsfixed,butitsdirectionmaychange.C.Thedirectionofremainsfixed,butitsmagnitudemaychange.D.remainsfixedinbothmagnitudeanddirection.3.Ifistheimpulseofaparticularforce,whatis?A.ThemomentumB.ThechangeinmomentumC.TheforceD.Thechangeintheforce4.Avariableforceactsonanobjectfromto.Theimpulseoftheforceiszero.OnecanconcludethatA.and.B.butpossibly.C.possiblybut.D.possiblyandpossibly.5.AsystemofNparticlesisfreefromanyexternalforces.Whichofthefollowingistrueforthemagnitudeofthetotalmomentumofthesystem?A.Itmustbezero.B.Itcouldbenon-zero,butitmustbeconstant.C.Itcouldbenon-zero,anditmightnotbeconstant.D.Theanswerdependsonthenatureoftheinternalforcesinthesystem.6.Thexandycoordinatesofthecenterofmassofthethree-particlesystemshownbeloware:A.0,0B.1.3m,1.7mC.1.4m,1.9mD.1.9m,2.5m7.BlockA,withamassof4kg,ismovingwithaspeedof2.0m/swhileblockB,withamassof8kg,ismovingintheoppositedirectionwithaspeedof3m/s.Thecenterofmassofthetwoblock-systemismovingwithavelocityof:A.1.3m/sinthesamedirectionasA.B.1.3mC.2.7m/sinthesamedirectionasA.D.1.0m/sinthesamedirectionasB.8.Alargewedgewithmassof10kgrestsonahorizontalfrictionlesssurface,asshown.Ablockwithamassof5.0kgstartsfromrestandslidesdowntheinclinedsurfaceofthewedge,whichisrough.Atoneinstanttheverticalcomponentoftheblock’svelocityis3.0m/sandthehorizontalcomponentis6.0m/s.Atthatinstantthevelocityofthewedgeis:A.3.0m/stotheleftB.C.6.0m/stotherightD.6.0m/stotheleft9.A1.0-kgballmovingat2.0m/sperpendiculartoawallreboundsfromthewallat1.5m/s.Thechangeinthemomentumoftheballis:A.zeroB.0.5N·sawayfromwallC.0.5N·stowardwallD.3.5N·sawayfromwallII)Fillintheemptyspacewithcorrectanswer1.Twoobjects,AandB,collide(碰撞).Ahasamassof,andBhasamassof.Thevelocitiesbeforethecollisionarem/sandm/s.Afterthecollision,m/s.ThefinalvelocityofBm/s.2.Astreamofwaterimpingeson(撞击)astationary“dished”turbineblade,asshowninFig.8.Thespeedofthewaterisv,bothbeforeandafteritstrikesthecurvedsurfaceoftheblade,andthemassofwaterstrikingthebladeperunittimeisconstantatthevalue.Theforceexertedbythewateronthebladeis___________.3.A320gballwithaspeedvof6.22m/sstrikesawallatangleθof30.0oandthenreboundswiththesamespeedandangle.Itisincontactwiththewallfor10.4ms.(a)Theimpulsewasexperiencedbythewallis.(b)Theaverageforceexertedbytheballonthewallis.4.Themuzzlespeedofabulletcanbedeterminedusingadevicecalledaballisticpendulum,showninFigure.AbulletofmassmmovingatspeedvencountersalargemassMhangingverticallyasapendulumatrest.ThemassMabsorbsthebullet.Thehangingmass(nowconsistingofM+m)thenswingstosomeheighthabovetheinitialpositionofthependulumasshown.Theinitialspeedv′ofthependulum(withtheembeddedbullet)afterimpactis.Themuzzlespeedvofthebulletis.III)CalculateFollowingProblems:1.Ablockofmassm1=1.60kginitiallymovingtotherightwithaspeedof4.00m/sonafrictionlesshorizontaltrackcollideswithaspringattachedtoasecondblockofmassm2=2.10kginitiallymovingtotheleftwithaspeedof2.50m/s,asshowninFigure.Thespringconstantis600N/m.(a)Attheinstantblock1ismovingtotherightwithaspeedof3.00m/s,asinFigure,determinethevelocityofblock2.(b)Determinethedistancethespringiscompressedatthatinstant.2.A3.00-kgsteelballstrikesawallwithaspeedof10.0m/satanangleof60.0°withthesurface.Itbouncesoffwiththesamespeedandangle.Iftheballisincontactwiththewallfor0.200s,whatistheaverageforceexertedontheballbythewall?3.Asmallballwithmassmisreleasedfromrestatthetopofacontainerwhichinsidewallissemicircle-shapedandfrictionless.ThecontainerwithmassMandradiusRrestsonafrictionlesshorizontalsurface,asshown.WhentheballslidestopointBatthebottomofthecontainer,findthenormalforceexertedbythecontainerontheball.AABChapter4WorkandEnergyI)Chooseonecorrectansweramongfollowingchoices1.Theworkdonebygravityduringthedescentofaprojectile:A.ispositiveB.isnegativeC.iszeroD.dependsforitssignonthedirectionoftheyaxis2.AparticlehasaconstantkineticenergyEk.Whichofthefollowingquantitiesmustalsobeconstant?()(A)(B)v(C)(D)3.A0.2kgblockslides(滑行)acrossafrictionlessfloorwithaspeedof10m/s.Thenetworkdoneontheblockis((A)-20J(B)-10J(C)0J(D)20J4.A0.50kgobjectmovesinahorizontalcirculartrackwitharadiusof2.5m.Anexternalforceof3.0N,alwaystangenttothetrack,causestheobjecttospeedupasitgoesaround.TheA.24JB.47JC.59JD.94J5.Amanpushesan80-Ncrateadistanceof5.0mupwardalongafrictionlessslopethatmakesanangleof30◦withthehorizontal.Hisforceisparalleltotheslope.Ifthespeedofthecratedecreasesatarateof1.5m/s2,thentheworkdonebythemanis:A.−200JB.61JC.140JD.200J6.Whenacertainrubberbandisstretchedadistancex,itexertsarestoringforceofmagnitudeF=ax+bx2,whereaandbareconstants.Theworkdoneinstretchingthisrubberbandfromx=0tox=Lis:A.aL2+bLx3B.aL+2bL2C.a+2bLD.aL2/2+7.Anidealspringishungverticallyfromtheceiling.Whena2.0-kgmasshangsatrestfromitthespringisextended6.0cmfromitsrelaxedlength.Adownwardexternalforceisnowappliedtothemasstoextendthespringanadditional10cm.Whilethespringisbeingextendedbytheforce,theworkdonebythespringis:A.−3.6JB.−3.3JC.3.6JD.3.3J8.Twoobjectswithmassesofm1andm2havethesamekineticenergyandarebothmovingtotheright.Thesameconstantforceisappliedtothelefttobothmasses.Ifm1=4m2,theratioofthestoppingdistanceofm1tothatofm2is:A.1:4B.4:1C9.Attimet=0a2-kgparticlehasavelocityof(4m/s)−(3m/s).Att=3sitsvelocityis(2m/s)+(3m/s).Duringthistimetheworkdoneonitwas:A.4JB.−4JC.−12JD.−40J10.A2-kgblockstartsfromrestonaroughinclinedplanethatmakesanangleof60owiththehorizontal.Thecoefficientofkineticfrictionis0.25.Astheblockgoes2.0mdowntheplane,themechanicalenergyoftheEarth-blocksystemchangesby:A.0B.−9.8JC.9.8JD.−4.9JII)Fillintheemptyspacewithcorrectanswer1.Achain(链条)isheldonafrictionlesstablewithone-fourthofitslengthhangingovertheedge,asshowninfigure.IfthechainhasalengthLandamassm,theworkrequiredtopullthehangingpartbackonthetableisJ.2.A0.1kgblockisdroppedfromaheightof2montoaspringofforceconstantk=2N/m,asshown.Themaximumdistancethespringwillbecompressedis_________m.(g=10m/s2)3.AsingleconstantforceNactsona4.00-kgparticle.(a)Iftheparticlemovesfromtheorigintothepointhavingthevectorpositionm,theworkdownbythisforceis.(b)Ifitsspeedattheoriginis4.00m/s,thespeedoftheparticleatis.(c)Thechangeinthepotentialenergyofthesystemis.III)CalculateFollowingProblems:1.A3.00-kgmassstartsfromrestandslidesadistanceddownafrictionless30.0°incline.Whilesliding,itcomesintocontactwithanunstressedspringofnegligiblemass,asshown.Themassslidesanadditional0.200masitisbroughtmomentarilytorestbycompressionofthespring(k=400N/m).Findtheinitialseparationdbetweenthemassandthespring.2.Twomassesareconnectedbyalightstringpassingoveralightfrictionlesspulleyasshown.The5.00-kgmassisreleasedfromrest.(a)Determinethespeedofthe3.00-kgmassjustasthe5.00-kgmasshitstheground.(b)Findthemaximumheighttowhichthe3.00-kgmassrises.Chapter5AngularmomentumandRigidbodyI)Chooseonecorrectansweramongfollowingchoices1.Aparticlemoveswithpositiongivenby,whereismeasuredinmeterswhentismeasuredinseconds.Foreachofthefollowing,consideronlyt>0.ThemagnitudeoftheangularmomentumofthisparticleabouttheoriginisA.increasingintime.B.constantintime.C.decreasingintime.D.undefined2.Asolidobjectisrotatingfreelywithoutexperiencinganyexternaltorques.InthiscaseA.Boththeangularmomentumandangularvelocityhaveconstantdirection.B.Thedirectionofangularmomentumisconstantbutthedirectionoftheangularvelocitymightnotbeconstant.C.Thedirectionofangularvelocityisconstantbutthedirectionoftheangularmomentummightnotbeconstant.D.Neithertheangularmomentumnortheangularvelocitynecessarilyhasaconstantdirection.3.A2.0-kgblocktravelsarounda0.50-mradiuscirclewithanangularvelocityof12rad/s.Themagnitudeofitsangularmomentumaboutthecenterofthecircleis:A.6.0kg·m2/sB.12kg·m2/sC.48kg/m2·sD.72kg·m24.A6.0-kgparticlemovestotherightat4.0m/sasshown.ThemagnitudeofitsangularmomentumaboutthepointOis:A.zeroB.288kg·m2/sC.144kg·m2/sD.24kg·m2/s5.Twoobjectsaremovinginthex,yplaneasshown.Themagnitudeoftheirtotalangularmomentum(abouttheoriginO)is:A.zeroB.6kg·m2/sC.12kg·m2/sD.30kg·m2/s6.A2.0-kgblockstartsfromrestonthepositivexaxis3.0mfromtheoriginandthereafterhasaconstantaccelerationgivenby.Attheendof2sitsangularmomentumabouttheoriginis:A.0B.(−36kg·m2/s)C.(+48kg·m2/s)D.(−96kg·m2/s)7.Asa2.0-kgblocktravelsarounda0.50-mradiuscircleithasanangularspeedof12rad/s.Thecircleisparalleltothexyplaneandiscenteredonthezaxis,adistanceof0.75mfromtheorigin.Thezcomponentoftheangularmomentumaroundtheoriginis:A.6.0kg·m2/sB.9.0kg·m2/sC.11kg·m2/sD.14kg·mII)Fillintheemptyspacewithcorrectanswer1.AparticlelocatedatthepositionvectormisactedbyaforceN.Thetorqueabouttheoriginshouldbe_______.2.Thevelocityofam=2kgbodymovinginthexyplaneisgivenbym/s.Itspositionvectorism.Itsangularmomentumabouttheoriginshouldbe___________.3.Twoparticleseachofmassmandspeedv,travelinoppositedirectionsalongparallellinesseparatedbyadistanced.Thetotalangularmomentumofthesystemaboutanyoriginis.4.Aparticleislocatedat=(0.5m)+(−0.3m)+(0.8m).Aconstantforceofmagnitude2Nactsontheparticle.Whentheforceactsinthepositivexdirection,thecomponentsofthetorqueabouttheoriginis,andwhentheforceactsinthenegativexdirection,thecomponentsofthetorqueabouttheoriginis.5.Auniformbeamoflengthlisinaverticalpositionwithitslowerendonaroughsurfacethatpreventsthisendfromslipping.Thebeamtopples.Attheinstantbeforeimpactwiththefloor,theangularspeedofthebeamaboutitsfixedendis.6.AdiskofmassmandradiusRisfreetoturnaboutafixed,horizontalaxle.Thediskhasanidealstringwrappedarounditsperipheryfromwhichanothermassm(equaltothemassofthedisk)issuspended,asindicatedinFigure.Themagnitudeoftheaccelerationofthefallingmassis,themagnitudeoftheangularaccelerationofthediskis.III)CalculateFollowingProblems:1.Thepulleyhasradius0.160mandmomentofinertia0.480kg·m2.Theropedoesnotsliponthepulleyrim.Useenergymethodstocalculatethespeedofthe4.00-kgblockjustbeforeitstrikesthefloor.mm,R2.Ablockwithmassmslidesdownasurfaceinclinedtothehorizontal.Thecoefficientofkineticfrictionisμ.Astringattachedtotheblockiswrappedaroundawheelonafixedaxis.ThewheelhasmassmandradiusRwithrespecttotheaxisofrotation.Thestringpullswithoutslippingmm,Ra)Whatistheaccelerationoftheblockdowntheplane?b)Whatisthetensioninthestring?3.AwoodenblockofmassMrestingonafrictionlesshorizontalsurfaceisattachedtoarigidrodoflengthlandofnegligiblemass.Therodispivotedattheotherend.Abulletofmassmtravelingparalleltothehorizontalsurfaceandnormaltotherodwithspeedvhitstheblockandbecomesembeddedinit.Whatistheangularmomentumofthebullet–blocksystem?Chapter9MechanicoscillationI)Chooseonecorrectansweramongfollowingchoices1.Aparticleonaspringexecutessimpleharmonicmotion.IfthemassoftheparticleandtheamplitudearebothdoubledthentheperiodofoscillationwillchangebyafactorofA.4.B.8.C.2.D.2.AparticleisinsimpleharmonicmotionwithamplitudeA.Attimet=0itisatx=-A/2andismovinginthenegativedirection,thentheinitialphaseis:A.2π/3radB.4π/3radC.πradD.3π/2rad3.AparticleisinsimpleharmonicmotionwithperiodT.Attimet=0itisattheequilibriumpoint.Ofthefollowingtimes,atwhichtimeisitfurthestfromtheequilibriumpoint?A.0.5TB.0.7TC.T4.AweightsuspendedfromanidealspringoscillatesupanddownwithaperiodT.Iftheamplitudeoftheoscillationisdoubled,theperiodwillbe:A.TB.2TC.T/2D.4T5.Thedisplacementofanobjectoscillatingonaspringisgivenbyx(t)=Acos(ωt+φ).Iftheinitialdisplacementiszeroandtheinitialvelocityisinthenegativexdirection,thenthephaseconstantφis:A.0B.π/2radC.πradD.3π/2rad－1/2A1/2A－1/2A1/2A1/2T－1/2A1/2A1/2T－1/2A1/2A1/2T－1/2A1/2A1/2TABCD7.Anobjectofmassm,oscillatingontheendofaspringwithspringconstantk,hasamplitudeA.Itsmaximumspeedis:A.B.C.D.II)Fillintheemptyspacewithcorrectanswer1.Thetotalenergyofasimpleharmonicoscillator(谐振子)withamplitudeAandforceconstantkis_________.2.Findtheinitialphases(初相)ofthesimpleharmonicmotionasshowninfigure.－－A==III)CalculateFollowingProblems:1.Anobjectoscillateswithsimpleharmonicmotionalongthexaxis.Itsdisplacementfromtheoriginvarieswithtimeaccordingtotheequation:.wheretisinsecondsandtheanglesintheparenthesesareinradians.(a)Determinetheamplitude,frequency,andperiodofthemotion.(b)Calculatethevelocityandaccelerationoftheobjectatanytimet.(c)Determinethemaximumspeedandmaximumaccelerationoftheobject.2.A50.0-gmassconnectedtoaspringwithaforceconstantof35.0N/moscillatesonahorizontal,frictionlesssurfacewithamplitudeof4.00cm.Find(a)thetotalenergyofthesystemand(b)thespeedofthemasswhenthedisplacementis1.00cm.Find(c)thekineticenergyand(d)thepotentialenergywhenthedisplacementis3.00cm.Chapter10WavesI)Chooseonecorrectanswe