XMS 2025 Physics Prelim P2 QP

This document consists of 21 printed pages and 1 blank page. [Turn over Preliminary Examination 2025 CANDIDATE NAME CLASS INDEX NUMBER PHYSICS Paper 2 Secondary 4 Express Setter: Mr. Koh Tat Siang Vetter: Ms. Kris Chua 6091/02 22 Aug 2025 1 hour 45 minutes Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your name, class and index number on the work you hand in. Write in dark blue or black pen. You may use an HB pencil for any diagrams or graphs. Do not use staples, paper clips, glue or correction fluid. Section A Answer all questions. Write your answers in the spaces provided. Section B Answer one question. Write your answers in the spaces provided. 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. For Examiner’s Use Section A 70 Section B Q ………. 10 Total 80 Parent’s Signature

2 XMSS/Physics/6091/02/Preliminary Examination 2025 Section A [70 marks] Answer all questions. Write your answers in the spaces provided. 1 Fig. 1.1 shows a water gun that makes use of pressure exerted by piston to spray water out of a nozzle. Fig. 1.1 (a) The cross-sectional areas of the piston and nozzle are 2.0 cm 2 and 0.080 cm2 respectively. If a force of 5.0 N is exerted on the trigger, calculate the force exerted on the water at the nozzle. force = ………………….. [2] (b) When the force of 5.0 N is applied, the piston moved a distance of 0.60 cm in 1.0 s. (i) Calculate the volume of water displaced by the piston when it is pushed in. volume = …………………. [1] (ii) Using your understanding of molecules, explain why the volume of water displaced by the piston is the same as the volume of water leaving the nozzle. …………………………………………………………………………………... …………………………………………………………………………………... …………………………………………………………………………………... [2] (iii) Hence or otherwise, determine the speed of the water leaving the nozzle. speed = …………………. [2] [Total: 7]

3 XMSS/Physics/6091/02/Preliminary Examination 2025 [Turn over 2 Fig. 2.1 shows a rectangular stone block (ABCD) held stationary in position by a wire. The wire is in line with side DA and attached to a wall. Fig. 2.1 The weight of the rectangular stone block is 500 N. CG is the centre of gravity of the rectangular stone block. T is the tension in the wire. (a) Explain what is meant by the centre of gravity. ………………………………………………………………………………………….. ………………………………………………………………………………………….. [1] (b) Mark and label on Fig. 2.1 the pivot of the system should the wire be cut. [1] (c) Calculate the moment due to the weight of the stone block about the pivot marked in part (b). moment = ………………………….. [2] (d) State the principle of moments. ………………………………………………………………………………………….. ………………………………………………………………………………………….. ………………………………………………………………………………………….. [1] wire 500 N 0.80 m 1.20 m

4 XMSS/Physics/6091/02/Preliminary Examination 2025 (e) Hence, or otherwise determine the magnitude of T. T = …………………………… [2] (f) Describe one force acting on the stone block that is not shown on Fig. 2.1. ………………………………………………………………………………………….. ………………………………………………………………………………………….. [1] [Total: 8] 3 (a) Fig. 3.1 shows a container in which hot coffee is served for takeout at a cafe. It has a thin plastic lid. The container is made of two layers of cardboard, as shown in Fig. 3.2. Fig. 3.1 Fig. 3.2 Explain how the features of the container keeps the coffee hot for a longer period of time. …………………………………………………………………………………............. …………………………………………………………………………………............. …………………………………………………………………………………............. …………………………………………………………………………………............. …………………………………………………………………………………............. …………………………………………………………………………………............. [3] layer of corrugated cardboard stuck to a layer of cardboard cross-sectional view of container plastic lid

5 XMSS/Physics/6091/02/Preliminary Examination 2025 [Turn over (b) Fig. 3.3 shows a steam cleaner that produces steam to clean carpets. Fig. 3.3 The water tank is filled with 1.6 kg water at 25 C. This water is heated until it boils and produces steam. The specific heat capacity of water = 4200 J/ (kg C) The specific latent heat of vaporisation of water = 2.3 × 106 J/kg Calculate the amount of energy needed to vapourise 0.90 kg of the water in the tank. energy =………………………. [3] [Total: 6]

6 XMSS/Physics/6091/02/Preliminary Examination 2025 4 Fig. 4.1 shows part of a page from a student’s notebook. The student attempted to list out all the components of the electromagnetic spectrum. Fig. 4.1 (a) List three errors in the student’s notes and state how it should be corrected. 1. 2. 3. …………………………………………………………………………………... …………………………………………………………………………………... …………………………………………………………………………………... [3] (b) X-rays is used in hospitals for the diagnosis of medical conditions such as fractures or tooth decay. State one other application of X-rays. ………………………………………………………………………………………….. ………………………………………………………………………………………….. [1] [Total: 4]

7 XMSS/Physics/6091/02/Preliminary Examination 2025 [Turn over 5 Fig. 5.1 shows a lightning bolt striking a lightning rod. Fig. 5.1 The strike lasts for 0.25 s and 30 coulombs of charge passes through the lightning rod during this time. The average potential difference across the lighting rod is 7.5 × 108 V for the duration of the strike. (a) Define potential difference. ………………………………………………………………………………………….. ………………………………………………………………………………………….. [1] (b) Calculate the power of the lightning rod during the strike. power = …………………. [2] [Total: 3] 6 A small volume of liquid soap is dispensed when the soap dispenser detects a hand underneath the nozzle as shown in Fig. 6.1. Fig. 6.2 shows the circuit that the LDR is connected to. A light source and a light dependent resistor (LDR) placed beside the nozzle. Fig. 6.1 Fig. 6.2 12 V LDR 5 000  P Q R A nozzle soap dispenser light source soap LDR sensor

8 XMSS/Physics/6091/02/Preliminary Examination 2025 (a) When no light shines on the LDR, the reading on the ammeter is 1.5 mA. Calculate (i) the resistance of the LDR. resistance = ……………………. [2] (ii) the potential difference across the LDR. potential difference = …………………….. [2] (b) When a hand is placed beneath the nozzle, light from the light source is reflected into the LDR. The resistance of the LDR when light shines on it is 1 000 . The electronic switch of the nozzle is activated to dispense soap when the potential difference across it is larger than 8.0 V. State and explain how the electronic switch should be connected to the circuit shown in Fig. 6.2. Show all required working clearly. ………………………………………………………………………………………..… ………………………………………………………………………………………..… ………………………………………………………………………………………..… ……