2023 SCGS 4IP EOY Physics P2

SINGAPORE CHINESE GIRLS’ SCHOOL END OF YEAR EXAMINATION 2023 YEAR FOUR INTEGRATED PROGRAMME CANDIDATE NAME CLASS 4 REGISTER NUMBER CENTRE NUMBER INDEX NUMBER PHYSICS Thursday 28 September 2023 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 21 printed pages and a blank page. For Examiner’s Use Section A 50 Section B 30 Total 80

2 SECTION A Answer all the questions in this section. 1 (a) Fig. 1.1 shows a toy helicopter. It can hover and travel through the air. Fig. 1.1 A student flies the toy helicopter on a journey from A to B to C to D at a constant height. The toy helicopter makes the journey in 40 s. Fig. 1.2 is a scale drawing of the path of the helicopter, viewed from above. D C Fig. 1.2 (to scale) (i) State the difference between distance and displacement.. …........................................................................................................................................... …………………………………………………………………………………………………….[1] (ii) Determine the average speed of the toy helicopter. Average speed = ......................................... [2] 40 m 10 m 35 m North A B

3 (iii) Another toy helicopter flies directly from point A to point D in 40 s. Explain why the magnitude of the average velocity of this toy helicopter is smaller than the answer in (a)(ii). ……………………………………………………………………………………………………… ……………………………………………………………………………………………………... ………………………………………………………………………………………………….[1] When the toy helicopter hovers at D, its motor fails and it falls. It reaches terminal velocity as it falls. Explain, in terms of the forces and acceleration, what happens as the helicopter falls and reaches terminal velocity. You may draw a diagram to illustrate your answer if you wish. ….............................................................................................................................................................. …............................................................................................................................................................. …............................................................................................................................................................. …............................................................................................................................................................. …............................................................................................................................................................ …............................................................................................................................................................ …............................................................................................................................................................ …..….................................................................................................................................................. [3] [ Total : 7 m ] (b)

4 2 (a) (b) A child’s toy consists of a flexible track and a model car. Fig. 2.1 shows a diagram of the toy. Fig. 2.1 The child first holds the car stationary at point A which is 0.45 m above the horizontal sections of track BC and FG. The mass of the car is 0.12 kg. The child then releases the car which travels towards point B. Both air resistance and friction between the car and the track are negligible. The gravitational field strength g is 10 N / kg. Calculate the change in gravitational potential energy (g.p.e.) of the car as it travels from A to B. change in g.p.e. = .............................................. [2] Calculate the speed of the car when it reaches B. speed = ......................................................... [2]

5 (c) After releasing it, the child expects the car to follow the track along the route ABCDEFG. In fact, the model car does not reach F. (i) Explain, in terms of energy, why the car does not go past D, which is also 0.45 m above the horizontal track. ..................................................................................................................................... ................................................................................................................................ [1] (ii) Immediately after being released at A, the car travels to B, to C and then to D. Describe the motion of the car after it reaches D. .................................................................................................................................... ............................................................................................................................... [1] [ Total : 6 m]

6 3 A curved, glass tube is open at one end and sealed at the other. A dense liquid is poured into the tube. The liquid traps air in the sealed end. Fig. 3.1 shows the tube, the liquid and the trapped air. Fig. 3.1 The difference between the liquid levels is h. At room temperature, h is 0.57 m.The density of the liquid is 1.4 × 104 kg / m3. The gravitational field strength g is 10 N / kg and the atmospheric pressure is 1.0 × 105 Pa. Calculate the pressure of the trapped air. pressure = ......................................................... [2] The trapped air in the tube is heated. (i) The height of the trapped air in the tube is x. Explain, in terms of molecules, why x changes when the air is heated. .................................................................................................................................................. .................................................................................................................................................. ………………………………………………………………………………………………………..… ……………………………………………………………………………………..