4E Phy Prelim 2021 P1

BOONLAYSECONDARYSCHOOL PRELIMINARYEXAMINATION 2021 Name ( ) Class Subject : PHYSICSPaperNo : 1SubjectCode : 6091/01Level : SECONDARYFOUREXPRESSDate/Day : 13SEPTEMBER/ MONDAYTime : 1145- 1245Duration : 1HOUR READTHESEINSTRUCTIONSFIRST Donot openuntil youaretoldtodoso. Writeinsoftpencil.Donotusestaples,paperclips,glueorcorrectionfluid.WriteyournameandindexnumberontheAnswerSheetinthespacesprovided. INFORMATIONTOCANDIDATES Therearefortyquestionsonthispaper.Answer allquestions.ForeachquestiontherearefourpossibleanswersA, B, CandD.Choosethe oneyouconsider correct andrecordyour choicein soft pencil ontheseparateAnswerSheet. Eachcorrectanswerwillscoreonemark.Amarkwillnotbedeductedforawronganswer.Anyroughworkingshouldbedoneinthispaper.Theuseofanapprovedscientificcalculatorisexpected,whereappropriate. Thisquestionpaperconsistsof13printedpages.

2 SectionA[40marks]Answer allquestions. Foreachquestion,therearefourpossibleanswersA, B, CandD.Choosetheoneyouconsidercorrectandrecordyourchoiceinsoft pencilontheseparateAnswerSheet. 1 Apendulumissetinmotionand25completeoscillationsaretimed.Thetimemeasuredis75s. WhatistheperiodofthependulumandthetimetakenforthependulumtoswingfromXtoY? period/s time/sA 0.17 0.33B 0.33 0.17C 1.5 3.0D 3.0 1.5 2 Acyclist,ridingataspeedof5.0m/s,brakeswithuniformdecelerationandstopsin3.0m.Howlongdoesthecyclisttaketostop? A 0.30s B 0.60s C 0.83s D 1.2s 3 Aliftmovesdownwardsataconstantaccelerationof2m/s 2 .Giventhatthelifthasamassof500kg,whatisthetensioninthecable?(Takeg=10N/kg) A 2500N B 4000N C 5000N D 6000N BLS/Prelim/2021/4E/Physics/6091/01

3 4 Whichgraphbelowshowscorrectlyhowthecar’sdisplacementwillchangewithtimewiththegivenvelocity–timegraph? A C B D 5 ThefigureshowsforceF1 andF2 exertedonawoodenblockplacedonaconcretesurface.Anotherforcewhichisthefrictionbetweentheblockandtheconcretesurfaceis3.0N. Which pair of forces for F1 and F2 causes the wooden block to move with anacceleration? F1 /N F2 /NA 3.0 6.0B 5.0 8.0C 6.0 10D 8.0 11 BLS/Prelim/2021/4E/Physics/6091/01

4 6 Ahollowrectangularblockhasthedimensionsshown. Theholeinthemiddlegoesallthewaythroughtheblock.Thedensityofthemetalis15g/cm 3 .Whatisthemassoftheblock? A 900g B 2100g C 3000g D 3600g 7 AuniformbeamXYisbalancedonapivotwithtwoweights,W1 andW2 hungatequaldistancesfromthepivot. ItisobservedthattheendYmovesdownwardwhenW1 isremoved.Whereshouldthepivotbeinordertobalancethebeamagain? 8 AnL-shapedrigidleverarmispivotedatpointZ.Threeforcesactontheleverarm,asshowninthediagram. WhatisthemagnitudeoftheresultantmomentoftheseforcesaboutpointZ? A 20Nm B 30Nm C 40Nm D 70Nm BLS/Prelim/2021/4E/Physics/6091/01

5 9 A5.0cmmercurycolumnissuspendedalongaglasstubeasshowninFig.9.1.Giventhatthelengthofthetrappedairis8.0cmandtheatmosphericpressureis75cmHg,what isthelengthof thetrappedairwhentheglasstubeisinvertedtothepositionshowninFig.9.2. A 7.0cm B 8.1cm C 9.1cm D 10.3cm 10 ThediagramshowsamanometerusedtodeterminethedensityofliquidM.WhenliquidMispouredintoonearm,thewaterlevelintheotherarmrises.IfthedensitiesofwaterandLiquidMare1000kg/m 3 and750kg/m 3 respectively,calculatethevalueofh. A 8cm B 10cm C 12cm D 14cm 11 Thefigurebelowshowsaboxbeingpushedusingaconstant forceof Fthroughadistanced. Theboxhasaweight of WandthereisatotalresistiveforceRactingagainstthebox. Whatistheusefulworkdoneonthebox? A Fd–Rd–WdB Fd+Rd+WdC Fd–RdD Fd–Wd BLS/Prelim/2021/4E/Physics/6091/01

6 12 Waterispumpedoutofatankbyanelectricmotorattherateof150kg/s.Thespeedofthewaterasitleavesthetankis20m/s.Whatisthepowerofthiselectricmotor?Takeg=10N/kg. A 18kW B 27kW C 30kW D 45kW 13 Avesselcontainsagas.Moregasisaddedintothevessel.Ifthetemperatureandthevolumeofthevesselarekeptconstant,whichstatementisnotcorrect? A Thepressureofthegasincreases.B Theintermoleculardistancedecreases.C Thetotalweightofthevesselincreases.D Theaveragekineticenergyofthemoleculesincreases. 14 A personplaceshistwofeet ontwoseparatesurfaces, bothinitiallyat theroomtemperature.Onesurfaceisawoollencarpetwhiletheotherisaceramictile.Whichofthefollowingbestdescribeshowthepersonwillfeel? A Thefootonthecarpetfeelswarmerbecauseittransfersheattothefoot.B Thefootonthetilefeelscoolerbecauseittransferscoldnesstothefoot.C Thefootonthecarpetfeelswarmerbecauseheattransferisslowerbythewool.D Bothsurfacesarefeltthesamebythepersonsincebothareatthesametemperatureinitially. BLS/Prelim/2021/4E/Physics/6091/01

7 15 Whichofthefollowingprocessesisanillustrationofheattransferbyonlyradiation? A Fromahotflametothewaterinasaucepan.B Fromthefilamentofanelectriclamptotheinnersurfaceofthebulb.C Fromthehotsurfaceofanelectriclamptotherestoftheroom.D Fromthesuntoearthatmosphere. 16 Alaboratorythermometergaveareadingof−1°Cand99°Cwheninsertedintomeltingiceandboilingwateratstandardatmosphericpressurerespectively.Whatistheerrorwhen the same thermometer is used to measure the difference between twotemperatures? A −1°C B 0°C C 1°C D 2°C 17 Apieceofwirehasanelectricalresistanceof2.0Ωinmeltingice,and2.5Ωinboilingwater.Whatistheresistanceat20°Cassumingthatresistancechangesuniformlywithtemperature? A 0.1Ω B 2.0Ω C 2.1Ω D 2.2Ω 18 Anice-cubehasamassof8.0g.Theice-cubeisat0°C.Heatfromthesurroundingsreachestheice-cubeatanaveragerateof1.30J/s.Howlongdoesittakefortheicetomeltcompletely?Specificlatentheatoffusionofwateris336kJ/kg. A 2.07s B 2070s C 3500s D 2070000s 19 2.0kgofwaterat10°Cismixedwith4.0kgofwaterat70°C.Ifnoheatislost,thetemperatureofthemixturewillbe A 20°C B 30°C C 40°C D 50°C 20 ThediagrambelowshowsawaveonastringwithtwopointsPandQmarked.Thewaveismovinginthedirectionshown. Whatwillhappennext? A Pwillmoveup.B Pwillmovedown.C Qwillmoveup.D Qwillnotmove. BLS/Prelim/2021/4E/Physics/6091/01

8 21 ThediagrambelowshowsthewavefrontsofrippletravellingforwardfromPtoQinarippletank.ThetimetoreachQfromPis6.0s. Whatisthefrequencyofthewave? A 0.17Hz B 0.83Hz C 6.0Hz D 30.0Hz 22 Arayoflightinaglassblockisincidentonaboundarywithairatanangleofincidenceof38°.Thecriticalangleatthisair-glassboundaryis38°.Whathappenstotherayoflightattheboundary? A Itispartlyreflectedbackintotheglassandpartyrefractedalongtheboundary.B Itispartyreflectedbackintotheglassandpartlyrefractedintotheair.C Itistotallyreflectedbackintotheglass.D Itistotallyrefractedintotheair. 23 Amanisstandingstillwhileaplanemirrorismovingawayfromhimataspeedof2.0m/s.Howfastdoesheseehisimagemovingawayfromhimself? A 1.0m/s B 2.0m/s C 4.0m/s D 8.0m/s 24 Ahospitalneedstosterilisemedicalequipment.Whichelectromagneticwavescouldbeused? A infra-redB MicrowavesC RadiowavesD Ultraviolet 25 Asoundwaveofwavelengthof0.50mtravelsataspeedof320m/sinair.Itentersaliquidanditswavelengthbecomes2.5m.Whatisthefrequencyofthesoundintheliquid? A 128Hz B 320Hz C 640Hz D 3200Hz BLS/Prelim/2021/4E/Physics/6091/01

9 26 Thediagramshowsthetraceproducedonacathode-rayoscilloscope(c.r.o.)byasound. Which trace is producedwhenboththeloudnessandthepitchof thesoundareincreased? A C B D 27 Staticshocksarecausedby A abuild-upandsubsequentdischargeofprotons.B abuild-upandsubsequentdischargeofelectrons.C abuild-upandsubsequentdischargeofneutrons.D abuild-upandsubsequentdischargeofcations. 28 Twooutofthreedifferentplasticrodswerechargedbyrubbing.Thefollowingresultswereobtainedwhentwooftherodsareplacedneareachother. RodXandRodYrepelled.RodXandRodZattracted.Whichofthefollowingshowthechargeoftherods? RodX RodY RodZA negative negative neutralB negative neutral positiveC positive negative positiveD positive positive positive BLS/Prelim/2021/4E/Physics/6091/01

10 29 AresistancewireXYisconnectedinacircuitasshown. WhathappenstothebrightnessofthelampsasthejockeyslidesalongtheresistancewirefrompointXtoY? A lampPwillbebrighter,whilelampQwillbedimmer.B lampPwillbedimmer,whilelampQwillhavethesamebrightness.C lampPwillbebrighter,whilelampQwillhavethesamebrightness.D lampPwillhavethesamebrightness,whilelampQwillbebrighter. 30 Howmuchchargeflowsthroughthe6Ωresistorin1second? A 1C B 2C C 3C D 4C 31 Two resistors of 6Ωand12Ωarearrangedinparallel. Apotential differenceisconnectedacrosstheterminalsXandY.Thecurrentinthe6Ωresi