BV 4NA Physics 2022 Prelim Answer Key

PRELIM 20224N Science PhysicsMARK SCHEME12345DBDAB678910AAADC1112131415ACACC1617181920BCCDC1aElectronic mass balance (or any acceptable apparatus)B11b8.4 g/cm3 B12a1.681.76B12bCorrectly plotted points(allow only one incorrect plotted point – minus 1 mark)Balanced line G2 G1 2c79.5 cmNote: According to graph of candidateG12dNo change in period.Mass does not affect the period of pendulum B1 B13a60 / 1.5= 40 N/cm2 M1A13b20 000 N/cm2 B13cForce will be lesser.Pressure required to push pin in soft wall is lesser.B1B14aBC – non-uniform decelerationB14b(8 x 12) + ½ (12 + 20) x 8= 96 + 128= 224 mM1A14c1.92 x 106 NmB14d1 m/s2 B14eiRadiowaveB14eii3 x 108 = 900 x 106 x Wavelength,  = 0.333 mM1A15ai 3 correct drawings(2 correct drawings – B1)B25aiiheating element heats air causing hot air to rise due to it being less denseB15aiiiMetal casing – shiny/silverOR casing made of insulated materialDoes not allow heat to lose to surroundings easilyNote: focus responses to metal casing only according to question statementB1B15biB = liquidD = solidNote: Both terms need to be correct for markB15biichange of state, no change in

temperatureenergy released to form bonds, no change in internal kinetic energyB1B16aSwitch to close by connecting to RB16biQ = It= 0.3 x 30 x 60= 540 coulombsM1A16biipotential difference = 6 Vcurrent = 0.15 AB1B16cIf one bulb is short circuited, the other bulb can still light up.B16dPower = I x V= 0.3 x 6= 1.8 W= 0.0018 kWCost = 0.0018 x 15 x 24 x 22= 14.26 centsM1A1