Jurong Prelim P2

EX JURONG SECONDARY SCHOOL 2024 GRADUATION EXAMINATION SECONDARY FOUR 4 CANDIDATE NAME CLASS INDEX NUMBER PHYSICS 6091/02 Paper 2 Structured and Free Response 12 August 2024 1 hour 45 min Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Do not open this booklet until you are told to do so. Write your Centre number, index number and name on all 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 Paper 1 (30%) MCQ [40 marks] Paper 2 (50%) SECTION A [70 marks] SECTION B [10 marks] SUB-TOTAL [80 marks] Paper 3 (20%) PRACTICAL [40 marks] OVERALL % [100 %] This document consists of 24 printed pages including this page. O

2 PHY/2/4(EXP)/GE/24 [Turn over] Section A [70 marks] Answer all the questions in this section. 1 Fig. 1.1 shows the core of a transformer. It is made from thin sheets of iron. Fig. 1.1 There are 200 sheets of iron in the core of the transformer. The thickness of the core using a measuring instrument is 50.00 mm (a) Identify the error that we are trying to eliminate by the method of averaging when we want to find the thickness of a single sheet of iron. ………………………………………………………………………………………………… [1] (b) Suggest and explain what measuring instrument is used to measure the thickness of the core. ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………………… ………………………………………………………………………………………………… [2] (c) The density of the iron in the core is 7.65 g/cm3. The mass of the core is 1.38 kg. Calculate the volume of the core. volume = …………………… [1] thin sheet of iron core of transformer

3 PHY/2/4(EXP)/GE/24 [Turn over 2 Two blocks A and B of mass 3.0 kg and 2.0 kg respectively are connected by an inextensible string that passes through a smooth pulley as shown in Fig. 2.1. When B is stationary on the table and the string is taut, A is released from rest. Assume air resistance is negligible. . Fig. 2.1 (a) (i) On Fig 2.1, draw and label the weights and tensions acting on blocks A and B respectively. [2] (ii) Considering both boxes to move at the same rate, calculate the acceleration of A. acceleration = …………………… [2] (b) The speed of A just before it reaches the ground is 6.0 m/s. Calculate the maximum height reached by B after it rises above the original height of block A as shown in Fig. 2.1. height = …………………… [2] B A 9 m

4 PHY/2/4(EXP)/GE/24 [Turn over] 3 Fig. 3.1 shows a barrier used at a car park. The beam can be raised and lowered by a man rotating it about its pivot. Fig. 3.1 The weight of the beam is 150 N. (a) Calculate the moment of the weight of the beam about the pivot. moment = …………………… [1] (b) When the weight W of the heavy weight acts at a distance of 0.6 m from the pivot, the barrier is horizontal and balanced as shown in Fig. 3.1. (i) State what is meant by the Principle of Moments. …………………………………………………………………………………………………. …………………………………………………………………………………………………. …………………………………………………………………………………………. [1] (ii) The man raises the barrier and the heavy weight slips to a distance of 0.8 m further from the pivot. This causes a problem for the man trying to lower the barrier to make it horizontal. Describe and explain the problem this causes for the man in lowering the barrier. …………………………………………………………………………………………………. …………………………………………………………………………………………………. …………………………………………………………………………………………………. …………………………………………………………………………………………. [2] heavy weight pivot W beam 150 N 1.8 m 2.5 m 4.3 m

5 PHY/2/4(EXP)/GE/24 [Turn over 4 A diver dives to a depth below the surface of the sea where the total pressure is 3.0 × 105 Pa. (a) State two possible factors that will affects the total pressure that the diver will experience. ………………………………………………………………………………………………… [1] (b) Given that atmospheric pressure is 1.0 × 105 Pa and density of the sea water is 1030 kg/m3, calculate the depth of the diver below the surface of the sea. depth = …………………… [2] (c) As the diver descends deeper, the environment grows darker because less light can penetrate the deeper water. The diver is wearing a dive computer to monitor the water pressure and observes that the screen of the dive computer becomes brighter as he descends. (i) Draw a labelled diagram of an electrical circuit setup within the dive computer that allows the change in brightness of the screen. Your diagram should include:  a possible power source  an input transducer that changes with the brightness of the environment  a light bulb.  Label clearly each electrical components in your proposed circuit. [1] (ii) Explain how your proposed electric circuit in (c)(i) allows the screen of the dive computer to become brighter as he descends. …………………………………………………………………………………………………. …………………………………………………………………………………………………. …………………………………………………………………………………………………. …………………………………………………………………………………………... [2]

6 PHY/2/4(EXP)/GE/24 [Turn over] 5 Fig. 5.1 shows a load suspended from a spring. Fig. 5.1 The load is pulled down a small distance below its equilibrium position to position A, as shown in Fig. 5.2. The load then moves up and down between position A and position B in Fig. 5.2. Fig. 5.2 Describe the energy store transfers which occur as the load moves: (a) from position A to the equilibrium position ………………………………………………………………………………………………………… ………………………………………………………………………………………………… [1] (b) from the equilibrium position to position B. ………………………………………………………………………………………………………… ………………………………………………………………………………………………… [1] spring load position B position A equilibrium position

7 PHY/2/4(EXP)/GE/24 [Turn over 6 Medical professionals sometimes rub ethanol over the skin of a patient. Ethanol evaporates readily at room temperature and has a low specific latent heat of vaporisation. (a) State whether the patient experiences heating, cooling or neither at the site where the ethanol is applied. Using ideas about molecules, explain your answer. statement ……………………………………………………………………………………………… explanation ……………………………………………………………………………………….…… ………………………………………………………………………………………………………...… ………………………………………………………………………………………………….. [2] (b) State and explain the effect on the rate of evaporation of ethanol when a fan blows air over the skin of the patient. ………………………