2024 CCHM Physics 6091 P1 & P2 (MS)

Answers 1a uniform / constant acceleration for 6.0 s B1 after 6.0 s zero acceleration Reject: constant speed / velocity B1 1b m = F / a OR m = Ft / Δv in any form i.e. m = 1880 (6.0) / (22.0 – 0) C1 m = 513 kg A1 1c s = area under graph numerical or algebraic i.e. s = ½ (3.0 + 9.0) x 22 C1 s = 132 m A1 1di rising of hot air / fluid and sinking of cold air / fluid OR circulation of air / fluid due to / with temperature differences B1 1dii High temperature spot on Earth OR Sun heats surface OR (hot) less dense air rises upwards B1 2a lamina is in the Earth’s gravitational field OR Earth exerts a gravitational force on lamina Accept: gravitational field strength B1 2bi M = F  ┴ d OR 0.040(10) x 0.08 OR 0.4 x 8 C1 0.032 Nm OR 3.2 N cm A1 2bii lamina moves clockwise (about the pivot) B1 it speeds up and then slows down OR it oscillates with decreasing amplitude B1 stops with G vertically / directly below H / pivot / nail B1 3ai mercury stops exerting a pressure / weight per unit area on gas when tube is horizontal B1 3aii All 3 points mentioned B2, 1 or 2 point(s) mentioned B1 • The gas particles are in continuous, random motion at high speeds. • They collide with the tube walls, exerting an (average) force on the wall. • The average force per unit area exerted by these gas particles give rise to pressure. B2 3b P= ρgh OR 40 800 seen i.e P = 13600 x 10 x 0.30 C1 Total pressure = 40 800 + 101 000 =142 000 Pa A1

4ai chemical (potential store) B1 4aii Energy transferred by (electrical) current / electrically (from chemical store of battery to kinetic store of motor) OR electrons (made to) move B1 work is done mechanically by the motor on the (back) wheel OR Energy is transferred mechanically from motor to (back) wheel B1 4b KE = ½ mv2 in any form i.e. KE = ½ (800/10)(5.5)2 C1 1210 J A1 4ci energy provided when power is 1 kW for 1 hour / 1000 W for 1 hour B1 4cii t = E / P OR 0.45 / 0.075 OR 450 / 75 C1 6.0 h A1 5ai ∆E = mc ∆  in any form i.e. E = 0.500 x 4200 x 3.5 C1 7350 J A1 5aii energy input = 13 x 600 = 7800 J C1 efficiency = useful energy (output) / total energy (input) (  100%) OR (7800 – 7350) / 7800 x 100 C1 5.77% A1 5b any one from: • temperature change is an underestimate due to energy losses • energy is transferred from the water (to air / beaker / bench / surroundings) • energy other than light transferred in lamp (filament / glass / internal structure) AWW: energy loss B1 6ai object within focal length B1 6aii Virtual images are formed from divergent rays OR rays that extend back behind lens to meet at point on image OR rays that do not meet / converge on a screen OR rays that appear to come from image B1 6bi ray through optical centre from top of object B1 ray parallel to axis from top of object to lens AND correctly refracted through lens