2025 ZHSS Physics Prelim Paper 2 QP

1 [Turn over ZHONGHUA SECONDARY SCHOOL PRELIMINARY EXAMINATION 2025 SECONDARY 4 EXPRESS Candidate’s Name Class Register Number PHYSICS 6091 /02 Paper 2 28 August 2025 1 hour 45 minutes Additional Materials: NIL READ THESE INSTRUCTIONS FIRST Write your name, class and register number in the spaces at the top of this page and on all separate answer paper used. Write in dark blue or black pen. You may use a pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. Section A Answer all questions. Write your answers in the spaces provided on the question paper. Section B Answer one question. For Examiner’s Use Write your answers in the spaces provided on the question paper. Section A 70 Section B 10 Total 80 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. Setter: Mr Tan Jun Hong and Mrs Ngiam-Fok Kar Yin Vetter: Sec 4E Pure Physics Teachers This document consists of 21 printed pages and 1 blank page.

2 Section A Answer all the questions in this section in the spaces provided. 1 A drone was initially flying towards the west at a velocity of 15 m/s at time, t = 0 s. It then decelerated uniformly until it came to a stop at t = 10 s. The drone then turned and its velocity increases at a uniform rate of 2.0 m/s 2 for another 12 seconds towards the east. (a) Sketch, in the axes provided below in Fig. 1.1, the velocity-time graph of the drone. Fig. 1.1 [2] (b) Calculate the deceleration of the drone at t = 0 s. deceleration = [1] velocity / ms-1 Time / s 20 10 0 -10 -20 -30 5 10 15 20 25

3 [Turn over (c) Calculate the average speed of the drone for the entire duration of flight. average speed = [2] 2 Fig. 2.1 shows a toy water rocket. Fig. 2.1 The rocket is half-filled with water and connected by rubber tubing to a pump. (a) Air is then pumped into the rocket so that the pressure of the air inside the rocket increases. Explain, in terms of particles, why the air in the rocket exerts a pressure on the walls of the rocket. [2]

4 (b) When the air pressure in the rocket is high, the rubber tubing is removed from the rocket. The water in the rocket is expelled downwards. Use Newton’s laws of motion to explain why the rocket begins to accelerate upwards.