RI 2024 A-Level H2 Phys Solution

RAFFLES INSTITUTION YEAR 5-6 PHYSICS DEPARTMENT 1 9749 H2 Physics 2024 GCE A-Level Suggested Solutions Paper 1 1 A ( ) ( ) π − − = ×× = × = ×× ≈× 22 6 17 2 217 9 2 12 Approximate area 4 10 10 5.0265 10 m 5.0265 10 10 Gm 5 10 Gm 2 B ≤≤ 10 tt Acceleration has a positive and constant value. Object’s velocity increases linearly in the positive direction. Gradient of v – t graph is positive. ≤≤12t tt At t = t1, acceleration immediately switches to a negative value and remains constant until t = t2. Object’s velocity decreases linearly in the positive direction. Gradient of v – t graph is negative. 3 C Taking upward as positive, ( ) ( ) = + = °+ − = 2 2 1 2 10 15sin40 1.62 2 11.9 s yy ys ut at tt t 4 B As the cylinder is in equilibrium and acted upon by three forces, the vector triangle formed by the three forces forms a close loop in one direction. Options (A) and (C) are out. 5 D = = 3 ...... (1)3 W kx Wk x = = = ∴= ' ' [ substitute eqn(1) here] 3 '3 W kx WWx Wk x xx 6 B When specimen is stretched under the tensile load from zero to a maximum value, the work done by the tensile force on the specimen is area under OPQT. When relaxed, the work done by the specimen is area under SRQT. Hence the net work done on the specimen = area OPQT − area SRQT = area OPRS.

RAFFLES INSTITUTION YEAR 5-6 PHYSICS DEPARTMENT 2 7 C Since the car is moving up the hill at a constant speed, Forward driving force of the engine uphill = F + component of weight downhill = + × × °=engine 600 900 9.81 sin10 2133.14 NF = ×= ≈ engine 2133.14 16 34130 W 34 kW P 8 D Work done on the gas is when the gas is compressed by an external force and its volume decreases i.e. RS and SP. 9 A dAngular velocity d r tt rt θω = = = l l 10 A ω π − =  × =  × = 2 27 2 1.3 10 2 2 24 3600 0.0344 m s towards the centre of the Ear th. car 11 A As GM rφ =− where M is the mass of the object and r is the distance between the object and points P or Q, the magnitudes of their individual gravitational potentials decrease as r increases. Q P PQ GM GM GMd r r rrφ ∆= − −− =   where d =rQ − rP. As P and Q move away from the object while maintaining the same separation, d is unchanged but rp rQ increases, hence ∆φ decreases. 12 A The change in momentum of the particle after collision with the wall (shaded) ( ) 2p mv mv mv∆= −− = , taking leftward as the positive direction. The average force that the particle exerts on the shaded wall = 22 2 p mv mv xtx v ∆ = =∆ . 13 D Heat loss by volume V of water = Heat gained by V/4 of water (60 ) ( 20) 4 52 C VVc cρ θ ρθ θ −= − = ° 14 C At t = 0, x = −x0, EK = 0 J. 0 0 22 2 K0 cos sin 1 sin2 xx t vx t E mx t ω ωω ωω =− = = 15 C In critical damping, the mass will reach equilibrium in the shortest time without oscillating. 16 C 2 1 P IA I r = ∝

RAFFLES INSTITUTION YEAR 5-6 PHYSICS DEPARTMENT 3 2 mars earth earth mars 211 mars 11 1