3.5 PHYSICS(232)
3.5.1 PhysicsPaper1(232/1)
SECTIONA(25marks)
Answerallthequestionsinthissectioninthespacesprovided.
1 Figure1showspartofthemainscaleandvernierscaleofaverniercallipers.
Figure1
Recordthereadingindicated. (1mark)
2 Stateonefactorthataffectstheturningeffectofaforceonabody. (1mark)
3 Figure2showssomeairtrappedbymercuryinaglasstube.Thetubeisinvertedinadish
containingmercury.
Figure2
Giventhattheatmosphericpressureis760mmHgandtheheightofmercurycolumninthe
tubeis600mm,determinethepressureoftheairtrappedinthetubeinmmHg. (3marks)
4 Anobjectofweight20Nattachedattheendofaspringcausesanextensionof0.5cmonthe
spring.
(a) Determinethespringconstantofthespring. (2marks)
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(b) Determinetheweightofanobjectthatwouldcauseanextensionof0.86cmwhen
attachedattheendofthesamespring. (1mark)
5 Statetwomeasurementsyouwouldtakeinanexperimenttodeterminetheupthrustofan
objectwhichisimmersedinafluid. (2marks)
6 Statehowthemeasurementsinquestion(5)areusedtodeterminetheupthrustoftheobject.
(1mark)
7 Figure3showsapieceofwoodfittedintoacopperpipeandapieceofpaperwrappedtightly
aroundthejunction.
Figure3
Itisobservedthatwhenaflameisappliedaroundthepaperatthejunction,thesideofthe
paperaroundthewoodburnsfirst.Explainthisobservation. (2marks)
8 Figure4showsauniformmetreruleofweightINwithtwoweightsof0.18Nand0.12N
suspendedfromitsends.
Figure4
Determinehowfarfromthe0.18Nweightapivotshouldbeplacedinordertobalancethe
meterrule. (3marks)
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9 Explainwhybrakesfailinahydraulicbrakingsystemwhenairgetsintothesystem.
60
(2marks)
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10 Figure5showsaBunsenburner.
Figure5
Explainhowairisdrawnintotheburnerwhenthegastapisopen. (3marks)
11 Figure6(a)and6(b)showcapillarytubesinsertedinwaterandmercuryrespectively.
Figure6(a) Figure6(b)
Itisobservedthatinwaterthemeniscusinthecapillarytubeishigherthanthemeniscusinthe
beaker,whileinmercurythemeniscusinthecapillarytubeislowerthanthemeniscusinthe
beaker.Explaintheseobservations. (2marks)
12 Statewhyitisnecessarytoleaveanairspaceinaclosedglassbottleofwaterwhenitistobe
keptinarefrigerator. (1mark)
13 Adropofblueinkisintroducedatthebottomofabeakercontainingwater.Itisobservedthat
aftersometime,allthewaterinthebeakerturnsblue.Nametheprocessthattakesplace.
(1mark)
SECTIONB(55marks)
Answerallthequestionsinthissectioninthespacesprovided.
14 (a) Statetwowaysinwhichthecentripetalforceonabodyofmassmcanbeincreased
(2marks)
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(b) Figure7showsanobjectattheendofalightspringbalanceconnectedtoapegusinga
string.Theobjectismovinginacircularpathonasmoothhorizontaltablewitha
constantspeed.
Figure7
(i) Statewhatprovidesthecentripetalforce. (1mark)
(ii) Indicatewithanarrowonthefigurethedirectionofthecentripetalforce.
(1mark)
(iii) Stateareasonwhytheobjectisacceleratingwhileitsspeedremainsconstant.
(1mark)
(iv) Giventhatthemassoftheobjectis0.5kganditismovingataspeedof8ms-1
ataradiusof2m,determinethereadingonthespringbalance. (3marks)
(c) Astonethrownverticallyupwardsreachesaheightof100m.Determinethe:
(i) initialvelocityofthestone. (2marks)
(Neglectairresistanceandtakeg=10ms-2)
(ii) totaltimethestoneisinair. (2marks)
15 (a) Statethemeaningoftheterm“specificlatentheatoffusion”. (1mark)
(b) Figure8showsasetupofapparatususedinanexperimenttodeterminethespecific
latentheatoffusionofice.
Figure8
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Thefollowingreadingswerenotedaftertheheaterwasswitchedonfor5minutes:
- massofbeaker = 130g
- massofbeaker+meltedice= 190g
(i) Determinethe:
(I) energysuppliedbythe60Wheaterinthe5minutes. (3marks)
(II) specificlatentheatoffusionofice. (4marks)
(ii) Itwasobservedthatsomeofthecrushedicemeltedevenbeforetheheaterwas
switchedon.Stateareasonforthisobservation. (1mark)
16 (a) Ahorizontalforceof12Nisappliedonawoodenblockofmass2kgplacedona
horizontalsurface.Itcausestheblocktoaccelerateat5ms-2.Determinethefrictional
forcebetweentheblockandthesurface. (3marks)
(b) Figure9showsagraphofvelocityagainsttimeforaballbearingreleasedatthe
surfaceofviscousliquid.
Figure9
Explainthemotionoftheballbearingforparts
(i) OA (2marks)
(ii) AB (2marks)
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(c) Figure10showsapulleysystemusedtoraisealoadbyapplyinganeffortof500N.
Figure10
Statethe:
(i) velocityratioofthesystem. (1mark)
(ii) purposeofpulley2. (1mark)
(iii) Giventhatthemachinehasanefficiencyof80%,determinethemaximum
loadthatcanberaised. (3marks)
17 Figure11showsaninsulatedcylinderfittedwithapressuregauge,aheatingcoilanda
frictionlesspistonofcross-sectionalarea100cm2.
Figure11
(a) WhilethepistonisatpositionO,thepressureoftheenclosedgasis10Ncm-2ata
temperatureof27°C.Whena10kgmassisplacedonthepiston,itcomestorestat
positionAwithoutchangeinthetemperatureofthegas.
(i) Determinethenewreadingonthepressuregauge. (4marks)
(ii) Statewithareasonhowthevalueobtainedin(i)compareswiththeinitial
pressure. (2marks)
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(b) Thegasisnowheatedbytheheatingcoilsothatthepistonmovesbacktotheoriginal
positionO.
(i) Statethereadingonthepressuregauge. (1mark)
(ii) Determinethetemperatureofthegasin°C. (4marks)
(Takeg=10Nkg-1).
18 (a) Figure12showsaweighingbalanceonwhichabeakercontainingsomewateris
placed.Thereadingonthebalanceis2.80N.Ametalblockweighing2.7Nis
suspendedfromaspringbalance.
Figure12
(i) Statewhatisobservedonthespringbalanceandtheweighingbalance,asthe
metalblockisgraduallyloweredintothewater.
(I) Observationonspringbalance. (1mark)
(II) Observationonweighingbalance. (1mark)
(ii) Explaintheobservationmadeonthespringbalancein(I). (2marks)
(iii) Whenthemetalblockisfullyimmersedinthewater,thereadingonthespring
balanceisfoundtobe2.46N.Determinethe:
(I) readingontheweighingbalance. (2marks)
(II) densityofthemetal. (3marks)
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(c) Figure13showsahydrometerwithathinstemfloatinginwaterinabeaker.
Figure13
Statewithareasonwhatisobservedonthehydrometerwhenthetemperatureofthewateris
raised. (2marks)
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3.5.2 PhysicsPaper2(232/2)
SECTIONA(25marks)
Answerallthequestionsinthissection.
1 Statethereasonwhywhenarayoflightstrikesamirrorat900,thereflectedraytravelsalong
thesamepathastheincidentray. (1mark)
2 Explainwhytheimageformedinapinholecameragetsblurredwhentheholeisenlarged.
(2marks)
3 Statethereasonwhythemagneticfieldstrengthofamagnetisgreatestatthepoles. (1mark)
4 Figure1showsacellofe.m.f.2VconnectedinserieswitharesistorRandaswitchS.
(a) StatethereadingofV1withSopen. (1mark)
(b) WithSclosed,V1reads1.6V.StatethereadingofV2. (1mark)
centreofcurvatureofthemirror.
Completethediagramtoshow:
(a) howincidentraysarereflectedtoformtheimage; (2marks)
(b) theobjectposition. (1mark)
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6 Figure3showsarayoflightpassingintoaglassprismABC.
(a) Determinethevaluesofaandb. (1mark)
(b) IdentifyX. (1mark)
8 Figure4showsasimpletransformerconnectedtoa12Va.c.sourceandana.c.voltmeter.
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Bycountingthenumberofturnsineachcoil,determinethereadingonthevoltmeter.
(3marks)
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9 Indomesticwiringsystemslampsinthelightingcircuitarerequiredtobeinparallelandnotin
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areconnectedinserieswithaswitch,acellandamilliameter.
observation. (2marks)
burningwoodiscutoffbytheglasssheet. (2marks)
12 AphotonofultravioletlighthavingenergyEfallsonaphotoemissivesurfacewhose
workfunctionisT.Writeanexpressionforthemaximumkineticenergyofthe
resultingphotoelectronintermsofEandT. (1mark).
13 Whenagermaniumcrystalisdopedwitharsenic,itbecomesanN-typesemiconductor.Explain
howthischangeoccurs. (2marks)
(Numberofelectronsintheoutermostshellforgermanium=4,Arsenic=5)
SECTIONB(55marks)
Answerallthequestionsinthissection.
14 Figure6showstwoconvexlensesAandBusedtoproduceamagnifiedvirtualimageofan
object.
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(a) DeterminethefocallengthoflensA.(Take1unittorepresent10cm).
(b) Statethefunctionof:
(1mark)
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(i) lensA (1mark)
(ii) lensB (1mark)
(c) Statehowthefunctionsin(b)areachievedby:
(i) lensA (1mark)
(ii) lensB (1mark)
(d) Determinethemagnificationproducedby:
(i) lensA; (2marks)
(ii) thewholesystem. (2marks)
15 (a) Explainhowapositivelychargedelectroscopegetsdischargedwhenthecapistouched
withafinger. (2marks)
(b) Figure7showscapacitorsAandBconnectedinserieswithabatteryofe.m.f4V.
Determine:
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.
(i)theeffectivecapacitanceofthecircuit.(3marks)
(ii)thequantityofchargeincapacitorA.(3marks)
(iii)thequantityofchargeincapacitorB.(1mark)
(c)Figure8showsanisolatednegativepointchargeQ.
Onthefigure,sketchtheelectricfieldpatternaroundthecharge.(2marks)
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16 (a) TwopointsAandBhaveapotentialdifferenceofVvolts.Qcoulombsofchargeflow
(i) theelectricalenergytransformedbetweenthetwopointsintermsofQ.
(1mark)
(ii) thepowertransformedintermsofQandt. (1mark)
(iii) showthatthepowertransformedisgivenbyP=IV. (2marks)
(b) Thelightingcircuitinahousehas20lampseachrated60W,240V.Determinewhether
afuserated4Acanbeusedinthecircuitwhenallthelampsareputon. (4marks)
17 (a) Figure9showsacathoderaytubeinwhichabeamofelectronsiscastonthescreen.
Figure9
(i) statehowtheelectronsareproducedinthetube. (1mark)
(ii) statehowtheelectronbeamisdetected. (1mark)
(iii) Statethereasonforhavingavariablepotentialdifference(p.d.)atthe:
(I) grid; (1mark)
(II) anodes. (1mark)
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(b) Figure10showsthewaveformofasignalappliedatthey-platesofanoscilloscope
whosetime-baseisswitchedtothescaleof2millisecondspercentimeter.
Determine:
(i) theperiodofthesignal; (2marks)
(ii) thefrequencyofthesignal. (3marks)
18 (a) Figure11showsplanelightwavesinairincidentonaconvexlenswhoseprincipal
focusisF,thewavesmovepastpointG.
Completethediagramtoshowthepatternoftheemergentwavesbetweenthelensand
pointG. (2marks)
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(b) Figure12showscrestsofcircularwaterwavesspreadingfromtwopointsAandB
Figure12
Giventhattheamplitudeofeachwaveis5cm,statewithareasontheamplitudesofthe
(i) C; (2marks)
(ii) D. (2marks)
(c) Figure13showsastandingwaveformedwhenastringoflength1.5mstretched
betweentwosupportsispluckedinthemiddle.
Figure13
(i) Explainhowthestandingwaveisformed. (3marks)
(ii) Determinethewavelengthofthestandingwave. (1mark)
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coilsinseries.
Onthefigure,indicate
(i) thenorthandsouthpolesoftheresultingmagnet (1mark)
(ii) thecompletemagneticfieldpatternbetweenthepoles. (1mark)
(b) Figure15showsthepermanentmagnetmadeinpart(a)above.
Acoilwoundlooselyonthemiddlelimbisconnectedinserieswithalowvoltagea.c.
andaswitch.Stateandexplaintheobservationmadeonthecoilwhentheswitchis
closed. (2marks)
positivelycharged.
(i) Nametheelectrolyteinthecell. (1mark)
(ii) Explainhow:
(I) Zincgetsnegativelycharged. (1mark)
(II) Coppergetspositivelycharged (1mark)
(iii) Statewhatconstitutesthecurrentwhenawireisusedtoconnectthezincplate
andthecopperplateexternally. (1mark)
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3.5.3 PhysicsPaper3(232/3)
Question1.ThisquestionconsistsoftwopartsAandB;attemptbothparts.
PARTA
Youareprovidedwiththefollowing:
-apendulumbob
-astop-watch
-twometrerules
-tworetortstands,twobossesandtwoclamps.
-somethread.
Proceedasfollows:
(a) Clamponemetrerulehorizontallyonthetwostandssothatthegraduationsareina
verticalplane.Suspendthependulumbobfromthemetrerulewithtwopiecesof
threadsothatthelengthofeachthreadfromthepointofsupportonthemetreruleto
thependulumbobis50cm.Seefigure1.Thelengthofeachthreadwillremain
50cmthroughouttheexperiment.Theheightofthemetreruleabovethebench
shouldbeatleast65cm.
inaplaneperpendiculartothelengthofthemetreruleandreleaseitsothatitoscillates
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(c) Repeattheprocedurein(b)forothervaluesofdshownintable1.Completethetable.
Table1
(4marks)
(d) (i) PlotagraphofT4(y-axis)againstd2. (4marks)
(ii) DeterminetheslopesSofthegraph. (2marks)
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K2
,determinethevalueofK.(2marks)
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PARTB
Youareprovidedwiththefollowing:
-onemeterrule
-apieceofthread
-stopwatch
Proceedasfollows.
(e) UsingthemeterrulemeasurethelengthLandbreadthbforthemagnet.
L=...... m
b=...... m (1mark)
(f) UsethebalancetomeasurethemassMofthemagnet.
M=...... kg. (1mark)
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3
2
(2marks)
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(h) Clampthemeterrulebetweenthetworesortstands.Usingapieceofthreadsuspend
inahorizontalplaneasshowninfigure2.
Keepawayallunnecessarymagneticmaterialsincludingvoltmeterformthis
averticalaxisthroughitscentreasshownbythearrows.Measurethetimetfor
(a) t=...... s
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(II) DeterminetheperiodToftheoscillations. (1mark)
G
Question2
ThisquestionconsistsoftwopartsAandB,attemptbothparts.
PARTA
Youareprovidedwiththefollowing
-avoltmeter
-acapacitor
-aswitch
-astopwatch
-fiveconnectingwires
-twocellsandacellholder
Proceedasfollows:
(a) Connectthecircuitasshowninfigure3.
Makesurethattheterminalsofthecapacitorandthoseofthebatteryarecorrectlyconnected,
capacitor.
thestopwatchsimultaneously.Stopthestopwatchwhenthevoltagehas
(d) Resetthestopwatchandclosetheswitch.Repeattheprocedurein(c)to
oftheothervaluesshownintable2.
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Table2
(3marks
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(e) (i) Onthegridprovided,plotagraphofVoltageV(y-axis)againsttimet,
Vo
2
(4marks)
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t=...... seconds (1mark)
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(f) DeterminetheresistanceRofthevoltmetergiventhat
t=0.693CRwhereCisthecapacitanceofthecapacitor.
(1mark)
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PARTB
Youareprovidedwiththefollowing:
-atriangularglassprism
-ametrerule
-a50gmass
-somehotwater
-somecoldwater
-somethread
-athermometer
-onestand,onebossandoneclamp
-abeaker
Proceedasfollows:
(g) Usingapieceofthreadsuspendthemetrerulefromtheclamponthestandandadjust
thepositionofthethreaduntilthemetrerulebalanceshorizontally.Notethisposition,
Oofthethread.(Thispositionofthethreadmustbemaintainedthroughoutthe
experiment).
(h) Usinganotherpieceofthreadsuspendtheglassprismfromthemeterruleatapoint
35cmfromO.Suspendthe50gmassontheoppositesideofOusinganotherpiece
ofthread.Adjustthepositionofthethreadattachedtothe50gmassuntilthemetre
rulebalancesoncemore.Seefigure4.
mass.
l1=...... cm (1mark)
(Takeg=10Nkg-1) (1mark)
80
(i) Putcoldwaterintothebeaker(approximatelythreequarter(34full).Withtheglass
balanceswhentheprismisfullysubmergedinthecoldwater.Seefigure5.
(I) l2=...... cm (1mark)
(II) DeterminetheweightW2oftheprisminthecoldwater. (1mark)
(j) MeasureandrecordthetemperatureT1ofthecoldwaterwhenthesystemisbalanced.
T1=...... oC (1mark)
(k) Nowpouroutthecoldwaterandreplaceitwithhotwater.Balancethemetrerule
at35cmfrom0.
issubmergedinhotwater.
l3=...... cm. (1mark)
(ii) MeasureandrecordthetemperatureT2ofthehotwater.
T2=...... oC (1mark)
(iii) DeterminetheweightW3oftheprisminhotwater. (1mark)
(l) Determinetheconstantkforthewatergiventhat:
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k= (w1-w2)-(w1-w3)
(w1-w3)(T2-T1)
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