CAMBRIDGE IGCSETM PHYSICS COURSEBOOK ANSWERSExam-style questions and sample answers have been written by the authors.In examinations,the way marks are awardedmay be different.Coursebook answersChapter 1Questions55.5×103kgm31 a Fill a measuring cylinder with enough60.05cm3water that it will cover the steel block andthe block of wood but not overspill.7 a 840cmGently immerse the steel block and recordb 0.29cmthe reading on the measuring cylinder.c215.4cm3Raise the steel block and allow anyd 1.88kgdrips of water to fall into themeasuring cylinder.8a16.7msGently place the wooden block intob2.5the measuring cylinder.9 a Any random error with starting orLower the steel block to immerse bothstopping the stopwatch would be dividedthe wooden and metal blocksby20.Record the new reading on theb Values are,reading down the column:measuring cylinder.0.000.0.905.1.255,1.615,1.770.2.025,Subtract the smaller reading from the2.220,2.395bigger reading to get the volume of thewooden block.How period of oscillation varieswith length of oscillatorb 18cm32 a 0.1mmb3.12×103cm3of1.503a0.215m,0.1025m,0.065m0.500.00b143×10-3m3c 1955kg/m30.0004a9.71×10-2gLength of string /mdb0.222cm3d Density is less than that of waterCAMBRIDGE IGCSETM PHYSICS COURSEBOOK ANSWERSExam-style questions9 Provided that the ship does not leak,theoverall density of the ship is less than the2B;density of water so will float;10 Measure and record the mass of lots ofdrawing pins (no need to count them but at5ai262mm-173mm=89mm:least 50).i88.5mm;Pour enough water into a measuring cylinderto immerse the drawing pins.Measure and6 Measure the thickness of a ream of paperrecord the volume of water;(500 sheets)and then divide by 500;Immerse the same drawing pins in the water7m=pV=2.24×7.5×2.6×0.1and measure and record the new volume;[l]=4.37g;Subtract the smaller volume from the bigger8 a i15.82gvolume to find the volume displaced by thedrawing pins.i15.90cm3:Calculate the density by dividing the mass ofiii 0.90 g/cm3;the drawing pins by the displaced volume;l]iv 0.85 g/cm3;colour of layerThickness of layer cmclear2.0blue3.5green2.9red1.62Cambridge IGCSETM Physics-Sang,Follows,Tarpey Cambridge University Press 2021CAMBRIDGE IGCSETM PHYSICS COURSEBOOK ANSWERSChapter 2Questions11a37.5min1a10.44m/sb 30minb He started from rest and had to accelerate7.5 minso he ran slower than his average speed sodhe must also have run faster.90232.2m/s803 a C70-Sofia'sjoumeybB604300m/sSpeed50Arun'skm/rjourney5114.3km/h;31.7m/s65.36×1011m=5.36×10'km=536 million km2078 minutes108a3.23s0b 6m/s0510152025303540c19.35mTime /min12 a B,D,Hb A,C,GJoins traffic jamJoinsd EDistancemotorwayTraffic moving again13Driver sees hazardDriver applies brakes0510152025303540Speed/15Constant decelerationTime/minm/s1010 a 40kmCar stopsb 5.0km/h0c 20123d Between C and D(between 5pm andTime/s5.30pm)eAt E(6 pm)f 6.15km/hg 20 km/h between D and ECambridge IGCSETM Physics-Sang,Follows,Tarpey Cambridge University Press 2021