2010《physics-1》普通物理学期中试卷试题

第1页（共4页）《PhysicsⅠ》课程期中考试试卷开课学院：理学院考试形式：闭卷允许带非存储计算器、纸质词典入场考试时间:2010年5月6日所需时间100分钟姓名专业学号组号I.Multiple-choice:(thereisonecorrectansweronly)1.Astoneisthrownhorizontallyandfollowsthepathxyz.Thedirectionoftheaccelerationofthestoneatpointyis:A．↓B．→C．↘D．↗2.Anobjectistravelingaroundacircularorbitwitha12mradius.Atoneinstantitsspeedis6m/sandisincreasingat4m/s2.Atthatinstantthemagnitudeofitsaccelerationis:A．2m/s2.B．3m/s2.C．4m/s2.D．5m/s23.Anobjectismovinginx-yplanewithamotionfunctionof22ˆˆ25rtitj,theobjectisA．MovinginalineB．MovingnotinalineC．MovingwithconstantvelocityinalineD．Movingwithconstantspeedinaline4.Aparticlemovesinxdirection,itstartsfromtheoriginalpositionwithavelocityofv0=2.Theaccelerationoftheparticleisa=6v(visthevelocityoftheparticle).ThemotionoftheparticleisdependentonA.322xttB.342xtt.C.614(1)3txeD.642txe5.Aparticlemovesinxdirection,itstartsfromtheoriginalpositionwithavelocityofv0=4.Theaccelerationoftheparticleisa=3+2x.Thevelocityoftheparticle,atx=2,isA.4B.23.C.25D.66.AparticlemovesinacirclewithradiusofR=0.0625m,itsmotionisdependenton320.5()SttSI.Themagnitudeofitsacceleration,att=1s,isA.3B.4.C.5D.6horizontalxyz第2页（共4页）7.Anobjectismovinginx-yplanewithamotionfunctionof2ˆˆ(105)10rtitj,themagnitudeofitstangentialandcentripetalaccelerationatt=1sisA.5,52B.52,5.C.52,52D.5,58.A2kgparticleisactedbyaconservationforceandstartstomovefromoriginalpointalongthexaxis.Thepotentialenergy,relativetotheconservationforce,isgivenbyU(x)=2x2-3x4,whereUisinjouleandxisinmeter.Whentheparticleisatx=1.0m,itsaccelerationandvelocityareA.4m/s2,1m/sB.-4m/s2,1m/sC.4m/s2,2m/sD.-4m/s2,2m/s9.Awheelstartsfromrestandhasanangularaccelerationgivenby(t)=6t2,wheretisinsecondandisinradianspersecond-squared.Afterithasturnedthrough10revitsangularvelocityis:A．63rad/s.B．75rad/s.C．89rad/s.D．130rad/s.10.AsmallballwithmassmandradiusrfromrestatthepositionshownandrotateswithoutslippingalongthelooptrackofradiusR(Rr).Whatisthesmallestvalueofysuchthattheballwillrotatewithoutlosingcontactwiththetrack?A.2RB.R/2C.7R/10D.3R/411.A4.0kgsolidwheel,rollingwithoutslippingonahorizontalsurface,hasarotationalinertiaaboutitsaxisgivenbyMR2/2,whereMisitsmassandRisitsradius.AforceisappliedtoapointR/3awayfromtheaxleandthecenterofmasshasanaccelerationof2.0m/s2.Ifthedirectionoftheappliedforceispositive,theappliedforceandthefrictionalforcebetweenthewheelandgroundareA.6.0N,2N.B.6.0N,-2NC.9.0N,-1.0ND.9.0N,1.0N12.Asmallsatelliteisinellipticalorbitaroundtheearthasshown.IfLdenotesthemagnitudeofitsangularmomentumandPdenoteslinearmomentum:A.L2L1andP2P1;B.L2L1andP2=P1;C.L2=L1andP2P1;D.L2=L1andP2P1;13.Asmallbeadcanslidewithoutfrictiononacircularhoopwitharadiusof0.10minaverticalplane.Thehooprotatesataconstantrateof4.0rev/saboutaverticaldiameter,asshowninthefigure.Theangleβ,atwhichthebeadisinverticalequilibrium,isA.80°B.81°C.82°D.83°FL1,P1L2,P2m,ryR第3页（共4页）14.AuniformrodoflengthLandmassMissupportedbyahingeatoneendandisfreetorotateintheverticalplane.Therodisreleasedfromrestinahorizontalposition.Aparticle,withmassofM/3,issupportedbyathinstringoflengthLfromthehinge.Afterthecollision,therodturnstogetherwiththeparticle,themaximumangularθmaxisA.40°B.45°C.50°D.55°15.Twowheelsrotatetogetheraboutacommonaxis.Thetotalmomentofinertiaofthewheelsis40kgm2.Twoobjectsareattachedtothewheelsasshowninthefigure.TheradiiofthewheelsareR1=1.2mandR2=0.4m.Ifm1=24kgandm2=32kgsuchtheangularaccelerationofthewheelsis(thepositivedirectionis“into”thepage)A.2.0rad/s2B.-2.0rad/s2C.-1.6rad/s2D.1.6rad/s216.Awheel,ofradiusR,rotateswithanangularvelocityofaboutitsaxis.Oneendoftheaxisissuspendedatapoint,3Rawayfromthecenterofwheel.Fromtopview,theprecessionspeedofthewheelrotatingaboutaverticalaxisisA.3gR,clockwiseB.6gR,clockwiseC.6gR,anticlockwiseD.3gR,anticlockwise17.Asolidsphererotateswithoutslippingonahorizontalsurface,theratioofitsrotationalkineticenergytoitstotalkineticenergyisA.28.6%B.40%C.66.7%D.71.4%18.Alargetankfilledwithwaterhasapipeinthebottom(thepipeisthinenough).Insteadyflow,thepressureatPpointis(AtmosphereisP0):A.gHP310;B.gHP320;C.gHP320;D.gHP310;19.Therearethreeparticlesinapoint-likeparticlesystem,eachmassism,andseparationbetweentheparticlesisd.Thebindingenergy(theenergyforseparatingthesystem)ofthe3-particlesystemduetothegravitationalforceisM/3max3RHH/3P第4页（共4页）A.23GmdB.23GmdC.232GmdD.233Gmd20.Whenawindblowsbetweentwocars,asignificantdropinpressurecanbecreated.Theairpressureisnormally1atminsidethebuilding,sothedropinpressurejustoutsidecancauseanattractforceonthecar.Thedensityofairis1.29kg/m3.Undera27m/swind,theforceexertedona23mcarisA.2821NB.2632NC.2438ND.2212NII.Calculationproblems(presentthenecessaryequationsinsolution):1.Twoparticlescombinedtogether,theinteractionpotentialbetweentheparticlesis0/0()rrrUrer.(1)Whatistheseparationbetweentheparticlesattheequilibriumcondition?(2)Howmuchenergyisneededtobreakthisparticlesystem?2.Asmallsolidspherewithradiusrrollswithoutslippingfromthetopofahemisphericalmoundshowninthefigure.TheradiusofhemisphericalmoundisR,andRr.Thesmallsolidsph