2024 SCGS 4 IP PHYSICS P2

1 SINGAPORE CHINESE GIRLS’ SCHOOL END-OF-YEAR EXAMINATION 2024 YEAR FOUR INTEGRATED PROGRAMME PHYSICS PAPER 2 Wednesday 2 October 2024 1 Hour 45 mins Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Section A Answer all questions. Section B Answer all questions. Question 11 has a choice of parts to answer. Candidates are reminded that all quantitative answers should include appropriate units. The use of an approved scientific calculator is expected, where appropriate. Candidates are advised to show all their working in a clear and orderly manner, as more marks are awarded for sound use of Physics than for correct answers. The number of marks is given in brackets [ ] at the end of each question or part question. Take g = 10 ms-2 or 10 Nkg-1 unless stated otherwise. This question paper consists of 23 printed pages and a blank page. For Examiner’s Use Section A 70 Section B 10 Total 80 CANDIDATE NAME CLASS REGISTER NUMBER

2 SECTION A Answer all the questions in this section. 1 A man standing in a hot air balloon released a ping pong ball as the balloon accelerated upwards at 2.0 m/s2. The upward speed of the balloon is 2.0 m/s at the moment the ping pong ball is released. The ping pong ball has the same velocity as the balloon when it is released. Fig. 1.1 shows how the velocities of the hot air balloon and the ping pong ball vary with time. Fig. 1.1 (a) Explain why the acceleration of the ping pong ball at its maximum height is 10 m/s2. ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… [2] (b) Describe the motion of the ping pong ball from the moment it is released until it reaches terminal velocity. ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… [2]

3 (c) Calculate the average velocity of the hot air balloon from t = 0 to t = 3.0 s. Average velocity of hot air balloon = …………………….. [3] [ Total : 7 m ]

4 2 Fig. 2.1 shows how the speed of a rocket SpaceX varies with time as it enters the gravitational field of a new Planet Y with negligible atmosphere. Fig. 2.1 ( not to scale) SpaceX has a total mass of 1.8 x 10 6 kg. Once it enters the atmosphere of Planet Y, it undergoes free fall for 8.0 s before its engine fires a continuous thrust to bring it to a gentle upright landing on the surface of Planet Y. (a) Calculate the weight of SpaceX on Planet Y. Weight = ……………………….. [2]

5 (b) At 8.0 s, a significant amount of liquid oxygen fuel undergoes combustion in the rocket engine to produce a constant thrust,T, to decrease the rocket’s speed of descent. (i) On Fig. 2.2, draw and label all the forces acting on SpaceX during its descent. You may ignore air resistance. . Fig. 2.2 [2] (ii) 1. Write an equation relating the forces in Fig. 2.2. ………………………………………………………………………………………….. 2. Calculate the magnitude of the thrust, T. Thrust = ……………………………….. [1] [2] (iii) The thrust produced by the engine is uniform throughout the descent. Explain why the deceleration from t = 8.0 s to t = 28.0 s increases in reality. ……………………………………………………………………………………………… ……………………………………………………………………………………………… ……………………………………………………………………………………………… [1] [ Total : 8 m ]

6 3 In a tourist attraction, a lift, powered by a motor, is used to carry tourists up and down a mine shaft. The set up is shown in Fig. 3.1. Fig. 3.1 The vertical distance travelled by the lift is 8.0 m and the lift travels at an average constant speed of 0.40 m/s along the 16 m mine shaft. The total mass of a fully loaded lift is 800 kg. Work done against friction along the 16 m shaft is 16 000 J. (a) Calculate the gain in gravitational potential energy when the lift travels from the bottom to the top of the mine shaft. gain in GPE = [2] (b) The efficiency of the motor is 80%. Calculate the energy required by the motor each time it brings the lift up the shaft. energy required = [1] (c) Calculate the rate at which energy is done by the motor. power = [2] [ Total : 5 m ]

7 4 A piece of stiff cardboard is stuck to a plank of wood by means of two sticky-tape “hinges”. This is shown in Fig. 4.1. Fig. 4.1 (a) The cardboard is lifted as shown, using a force applied either at A or B or C. (i) On Fig. 4.1, draw the force at the position where its value will be as small as possible. State the angle between the force and the cardboard. Indicate this angle clearly on Fig. 4.1. Angle = ………………………… [1] (ii) Explain why the position you have chosen in (a)(i) results in the smallest force. ..………........................................................................................................................... ….……………………………………………………………………………………………[1] (b) Initially, the cardboard is flat on the plank of wood. A box of matches is placed on it. The cardboard is then slowly raised at the left hand edge, as shown in Fig. 4.2. Fig. 4.2 stiff cardboard sticky-tape “hinge” A B C stiff cardboard sticky-tape “hinge” plank of wood plank of wood

8 By means of a labelled diagram, explain the position of the matchbox when it is about to topple. ..………………………………………………………………………………………..……….. ........................................................................................................................................ …............................................................................................................................... [2] (c) The box of matches is opened, as shown in Fig. 4.3. The procedure in (b) is repeated. Fig. 4.3 Is the angle through which the cardboard can be lifted before the box of matches falls greater, the same or less than the angle before the box of matches falls in Fig. 4.2? Explain. Angle is …........................ the angle before the box of matches falls in Fig. 4.2. Explanation ........................................................................................................................................... ………………………………...…………………………………………………………………[2] [ Total : 6 m ]

9 5 A student uses a pump to inflate a bicycle tyre. Fig. 5.1 shows the pump and the tyre. Fig. 5.1 (not to scale) (a) The pressur