2021_PRELIM_4E_PHYSICS EOC_MS_V2

2021PRELIMINARYEXAMINATIONEOCPHYSICS ANSWERSCHEME Question Answer Marks 1(a)(i) MMO L=2.1±0.1cm 1 1(b)(i) MMO L1 =6.1±0.1cm ACE e=L1 –L=4.0cm(1d.p) 1 1(b)(ii) ACE T=ke=0.25x4.0=1.0N(2s.f) 1 1(c)(i) MMO x=60.0cm y=40.0cm z=80.0cm 1 1(c)(ii) ACE CorrectcalculationofWR withuniti.e.WR =0.50N 1 1(d) P correctconstant andindependentvariable changethedistancexwherethemassWishanged measureextensione(dependent)variableanddoesappropriatecalculation.CalculateupwardforceT=ke plotsgraphofTvsx WR correctlyrelatedtographi.e.y-intercept 5

2(a)(i) MMO Vo =2.30±0.2V 1 2(a)(ii) MMO I=0.24±0.02A 1 2(b)(i) ACE Arrangementofresistorsinseries 1 2(b)(ii) ACE Arrangementofresistorsinparallel 1 2(c)(i) MMO I=0.12±0.02A V=0.40±0.2V 1 2(c)(ii) MMO I=0.22±0.02A V=2.00±0.2V 1 2(c)(iii) PDO WhenRincreases,valuesofIdecreases(correctto0.01A) WhenRincreases,valuesofVdecreases(correctto0.05V) Arrangementofresistorstallywithvalueofcombineresistance 1 1 1 2(d) ACE SmallchangeofVinexperimentwillnotbedetectedusingvoltmeterthatgivesreadingsto0.1Vonly 1 3(a) MMO d=1.3±0.2cm 1 3(c)(i) MMO v=82.0±0.2cm 1

3(c)(i) MMO D=5.7±0.2cm 1 ACE CorrectcalculationforaveragediameterDwithunit 1 3(c)(iii) ACE ● TakeafewreadingsofDwithdifferentorientations● AveragethereadingsofD 2 3(c)(iv) ACE Correctcalculationofmi.e.m=4.4(2s.f) 1 3(d) PDO Correctlylabelledtableswithunitsi.e.x,v,D,m Atleast6setsofdata Degreeofaccuracyforv,Dandm 1 1 3 3(e) PDO Correctlylabelledaxes Scalingofgraph Correctlyplottedpoints(allcorrectlyplottedpoints–2,onlyoneincorrectlyplottedpoint–1) Drawingofbest-fitline 1 1 2 1 3(f)(i) ACE Workingforgradient CorrectcalculationofG(3s.f) 2 3(f)(ii) ACE Correctcalculationof1/Gi.e.1/G=18.0±2.0(3s.f) 1 Note: MMO–Manipulation, MeasurementandObservationPDO–PresentationofDataandObservationACE–Analysis, ConclusionsandEvaluationP-Planning