Dunman Sec 2024 Sec 4NA 5105 Prelims MS

1 2024 PRELIMINARY EXAMINATION SECONDARY 4 NORMAL (ACADEMIC) SCIENCE (PHYSICS) 5105 MARKING SCHEME PAPER 1 1 2 3 4 5 6 7 8 9 10 A A D D B B B A B C 11 12 13 14 15 16 17 18 19 20 C D B C B C D B B B PAPER 2 Section A Question Marking scheme Marks 1(a) and (b) [B1] correct plotting of all points [B1] correct drawing of best fit line (c) time = 2.5 s (ecf from best fit line drawn) [B1] (d) average speed = total distance / time = 30 / 5 = 6.0 m/s [B1]

2 2(a) 1 Both are transverse waves. 2 Both travel in vacuum at the same speed. OR any other acceptable answers [B1] [B1] (b) v = fλ f = v/λ = (3 × 108) / (1.0 × 10–11) = 3.0 x 1019 Hz [B1] (c)(i) charge: no change mass: no change [A1] [A1] (ii) Lead. Lead is able to absorb gamma radiation. [A1] [B1] 3(a) [A1] (b) Total pd across both lamps = 2 x 2.0 = 4.0 V Since e.m.f of the battery is equal to the sum of the pd across the both lamps, the e.m.f. of the battery = 4.0 V [M1] [A1] 4(a) quantity suitable apparatus length of 8.5 cm digital calipers [A1] mass of 4.8 g electronic balance [A1] (b)(i) Volume = length x breadth x height = 8.5 x 5.0 x 1.0 = 42.5 cm3 = 43 cm3 (2sf) [B1] (ii) density = mass / volume = 4.8 / 42.5 = 0.11 g/cm3 (2sf) [B1] (c)(i) [B1] correct drawing and label of normal [B1] correct drawing and label of weight (ii) 5.0 N. Since the block is moving with a constant speed, its acceleration is zero . As F - f = ma and that a=0.0 m/s 2, the friction will be equal to the applied force of 5.0 N. [A1] [B1] √ weight normal

3 PAPER 2 Section B Question Marking scheme Marks 5(a) chemical potential store [A1] (b) The internal energy increases. As the temperature increases, the kinetic store of the gas increases. Since internal energy depends on kinetic store, it also increases. [A1] [B1] (c)(i) Infrared radiation [A1] (ii) As the infrared radiation reaches the shiny metal surface, it gets reflected to the man. This allows the transfer of thermal energy to be more efficient and helps the man to absorb more thermal energy. [B1] [B1] (iii) 1 White is a poor emitter of infrared radiation. Heat loss from the man to the surroundings through radiation is reduced. 2 Air is trapped in the wool. Since air is a poor conductor /good insulator of heat, heat loss from man to the surroundings is minimised. [B1] [B1] 6(a) X: live wire To disconnect the live wire from the high voltage so that it is electrically isolated. [A1] [B1] (b) Z: earth wire To allow the high current to flow to the earth when the metal casing becomes live when there is a fault. [B1] [B1] (c)(i) Current flowing in the motor, I = P/V