4E Phy Prelim 2021 P3

BOONLAYSECONDARYSCHOOLPRELIMINARYEXAMINATION2021 Name ( ) Class Subject : PHYSICSPaperNo : 3SubjectCode : 6091/03Level : SECONDARYFOUREXPRESSDate/Day : 31AUGUST/ TUESDAYTime : 0815-1005Duration : 1HOUR50MINUTES READTHESEINSTRUCTIONSFIRST Writeyournameandindexnumberonalltheworkyouhandin.Writeindarkblueorblackpen.Youmayuseasoftpencilforanydiagrams,graphsorroughworking.Donotusestaples,paperclips,highlighters,glueorcorrectionfluid.Answer allquestions.ThePracticalExaminationisdividedintotwosections.Youareadvisedtospendnomorethan55minutespersection. Youwillstartwithonesectionandtherewillbeachangeover of equipment,55minutesafterthestartofthepaper. Youareexpectedtorecordallyourobservationsassoonastheyaremade.Anaccountofthemethodofcarryingouttheexperimentisnotrequired,unlessotherwisestated.Theuseofanapprovedscientificcalculatorisexpected,whereappropriate.Attheendoftheexamination,fastenallyourworksecurelytogether.Thenumberofmarksisgiveninbrackets[]attheendofeachquestionorpartquestion. For Examiner’sUse 1 2 3 Total Thisquestionpaperconsistsof12printedpages.

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3 SectionA 1 Inthisexperiment,youwillinvestigatetheamplitudeofasimplependulum. Youareprovidedwith ● apendulumbobattachedtoalengthofstring,● asplitcork,● astand,bossandclamp,● astopwatch,● ametrerule,● acounterweighttopreventthestandfromtoppling,● apieceofcardmarkedwithaseriesofparallellines,drawnat2cmintervals. Theapparatushasbeensetupforyou,asshowninFig.1.1(a)andFig.1.1(b) Fig. 1.1(a)(frontview) Fig. 1.1(b)(sideview) (a) (i) Thedistancefromthebottomof thesplit corktothecentreof thependulumbobisH.LoosentheclampandadjustthestringuntilHisequalto1.25m.Tightentheclamp. (ii) Adjustthebosssothatthedistancehfromthebottomofthependulumbobtotheflooris2.0cm. BLS/Prelim/2021/4E/Physics/6091/03

4 1 (b) Viewthependulumfromthefront,asshowninFig.1.1(a).Movethependulumbobafewcentimetrestotheside.Releasethependulumbobsothatitswingsfreely. DetermineanaccuratevaluefortheperiodTofthependulum. T=………………………………[2] (c) (i) Stopthependulum.Placethepieceofcardonthefloorbeneaththependulumbob.Thelinesonthecardaredrawnat2cmintervals. Adjustthepositionofthecarduntiltherighthandedgeofthependulumbobisalignedwiththe0cmmarkonthecard,whenviewedfromabove,asshowninFig.1.2. Fig. 1.2(viewfromabove) (ii) Movethependulumbobtothesideuntil theright handedgeof thebobisalignedwiththe12cmmarkonthecard,asshownbythedottedlineinFig.1.2. Releasethependulumbob.Measureandrecordthetimetfortheamplitudeofthependulumtodecreasefrom12cmto10cm. t=…………………………………[1] (iii) Suggestwhytheamplitudeofthependulumdecreases. …………………………………………………………………………………………….. BLS/Prelim/2021/4E/Physics/6091/03

5 ……………………………………………………………………………………….....[1] 1 (d) Plan Astudentsuggeststhatthetimetakenfortheamplitudetodecrease,asin(c)(ii),isdirectlyproportionaltothemassofthependulumbob. Plananexperimenttoinvestigatethisrelationship. Yourplanshouldinclude ● thequantitiesthatyouwillkeepconstant, ● adetaileddescriptionofhowyouwillperformtheinvestigation, ● anindicationofhowyouwillachieveaccurateresults, ● astatementofthegraphyouwouldplottotesttherelationship, ● asketchofthegraphyouwouldobtainifthesuggestedrelationshipiscorrect. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. BLS/Prelim/2021/4E/Physics/6091/03

6 ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ………………………………………………………………………………………………….. ……………………………………………………………………………………………....[6] BLS/Prelim/2021/4E/Physics/6091/03

7 2 Inthisexperiment,youwillinvestigatetheextensionofaspring. Youhavebeenprovidedwith ● alengthofstringtiedtoaspring,● anS-hook,● astand,bossandclamp,● apieceofplasticpipe,● amassofweight1.5N,● asetsquare,● a30cmruler,● a50cmrule,● ametrerulefixedtothebenchwithBlu-Tack,● aloopofstringonthemetrerule. (a) (i) Measureandrecordtheunstretchedlength l0 ofthespring,asshownin Fig.2.1. Fig. 2.1 l0 =………………………[1] (ii) Placeoneoftheloopsofthespringontotherodoftheclamp,asshowninFig.2.2.Suspendthemassontheotherloop. Fig. 2.2 Measureandrecordthestretchedlengthls ofthespring.Determinetheextensione0 ofthespringusingtheequatione0 =ls –l0 . ls =…………………………[1] e0 =…………………………[1] BLS/Prelim/2021/4E/Physics/6091/03

8 2 (b) Useyour valueof e0 from (a)(ii)andtheequationF=ke0 ,whereF=1.5N,todeterminethespringconstantkforthespring. k=…………………………[1] (c) Removethespringfromtherodoftheclamp. Placetheplasticpipeintheclamp.Adjusttheheightofthebosssothatthecentreoftheplasticpipeis50cmabovethebench.Adjustthepositionoftheclampstandsothatthecentreoftheplasticpipeisalignedwiththe50cmmarkonthemetrerule. AttachtheS-hooktotheloopofthestringonthemetrerule.AttachthespringtotheS-hook.Placethestringovertheplasticpipeandsuspendthemassfromtheloopattheendofthestring,asshowninFig.2.3. Fig. 2.3 BLS/Prelim/2021/4E/Physics/6091/03

9 2 (c) (i) Adjust thepositionoftheloopofstringonthemetreruleuntilthespringisvertical. Measureandrecordthestretchedlengthl1 ofthespring.Determinetheextensione1 ofthespringusingtheequatione1 =l1 –l0 . l1 =………………………… e1 =…………………………[1] (ii) Withthemassstillsuspendedfromthestring,carefullymovetheloopofstringonthemetrerulesothatitisatthe15cmmark. Measureandrecordthestretchedlengthl2 ofthespring.Determinetheextensione2 ofthespringusingtheequatione2 =l2 –l0 . l2 =………………………… e2 =…………………………[1] (d) Useyourvalueofk,valuesofe1 ande2 andtheequationfrom(b)tocalculatetheforcesF1 andF2 inthespringwiththeloopinthetwodifferentpositionsonthemetrerule. F1 =…………………………[1] F2 =…………………………[1] (e) ExplainwhyneitherF1 norF2 isequaltotheweightofthemassonthespring. …………………………………………………………………………………………............ …………………………………………………………………………………………………. ………………………………………………………………………………………………[2] BLS/Prelim/2021/4E/Physics/6091/03

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