NYGH-2023-S4-EOY-Physics-P2

Class Register Number Name End-of-Year Examination 2023 Secondary 4 PHYSICS Paper 2 Theory 1 hour 45 minutes Monday 9 Oct 0845 – 1030 No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your name, register number and class 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 tape/fluid. Write your answers in the spaces provided on the question paper. Section A (40 marks) Answer all questions. Section B (30 marks) Answer all questions. Question 13 has a choice of parts to answer: 13 Either or 13 Or. Circle Question 13 Either or 13 Or in the grid on the right to indicate which question you have answered. All quantitative answers should include appropriate units . The use of an approved scientific calculator is expected, where appropriate. Show all your working in a clear and orderly manner, as more marks are awarded for sound use of Physics than for correct answers. You are advised to spend no longer than one hour on Section A and n o longer than 45 minutes on Section B. The number of marks is given in brackets [ ] at the end of each question or part question. Take the acceleration due to gravity to be 10 m s -2 or gravitational field strength to be 10 N kg-1 near the Earth’s surface. Examiner’s Use Paper 2 (70 marks) Section A 1 2 3 4 5 6 7 8 9 10 Section B 11 12 13 Either 13 Or Total Paper 1 (30 marks) Overall 100 This document consists of 22 printed pages. Setters: AJL & LSH NANYANG GIRLS' HIGH SCHOOL [Turn over

2 Section A (40 marks) Answer all questions in this section. 1 A boy standing on a building throws a stone vertically upwards. Fig. 1.1 shows the variation of the velocity of the stone with time t. The stone leaves the boy’s hand at t = 0 s and reaches the ground at the bottom of the building at t = 2.8 s. Fig 1.1 (a) (i) Distinguish between velocity and speed. ……………………………………………………………………………………..………… ………………………………………………………………………………………..…... [ 1] (ii) Calculate the change in velocity of the stone between t = 0 s and t = 2.8 s. change in velocity = …………………….. [1] (iii) Calculate the change in speed of the stone between t = 0 s and t = 2.8 s. change in speed = …………………….. [1] -10.0 -5.0 0.0 5.0 10.0 15.0 20.0 0.00 0.50 1.00 1.50 2.00 2.50 3.00 velocity / m s−1 t / s

3 [Turn over (b) The displacement of the stone is 0 m at t = 0 s. Taking this as the reference position, (i) calculate the displacement of the stone at its maximum height, displacement = …………………….. [ 1] (ii) calculate the displacement of the stone when it reaches the ground. displacement = …………………….. [ 2] (iii) Hence, on the axes in Fig. 1.2, sketch the variation of the displacement of the stone with t from the instant the stone is at its maximum height until it reaches the ground. Label all relevant values clearly. [2] Fig. 1.2 displacement / m t / s

4 2 A plank of mass 5.0 kg is held horizontally by supports A and B. Support A is 80 cm from the centre of gravity C of the plank and support B is 30 cm from C, as shown in Fig. 2.1. A load of weight 25 N is placed at 60 cm from C. Fig 2.1 (a) State what is meant by [1] (i) the mass of an object. ………………………………………………………………………………………..…... ..... (ii) the weight of an object. ………………………………………………………………………………………..…... ..... (b) Calculate the force exerted on the plank by support A. force = …………………….. [ 2] (c) Hence or otherwise, calculate the force exerted on the plank by support B. force = …………………….. [ 1] A B C 60 cm 80 cm 30 cm 25 N

5 [Turn over 3 To determine the density of an unknown liquid X, a student measures its mass and volume. The readings are recorded in Table 3.1. Table 3.1 volume of liquid X / cm3 17.0 total mass of the measuring cylinder and liquid X / g 66.45 mass of the empty measuring cylinder / g 52.00 (a) Calculate the density of liquid X. density = …………………….. [ 2] (b) Fig. 3.1 shows an open U-shaped glass tube filled with water and liquid X. Fig. 3.1 The density of water is 1.0 g cm−3. Calculate the height h of the liquid X column. height = …………………….. [ 2] water liquid X 5.0 cm h 12.0 cm

6 4 Fig. 4.1 shows a solar water heater which is mounted on top of a roof. Cold water from the bathroom inside the house is carried by the pipe to the roof and hot water produced is returned to the bathroom. Fig. 4.1 (a) State the process by which thermal energy is transferred [1] (i) from the Sun to the Earth: ……… ………… ………………………………. (ii) through the pipe to the water: ……… ………… ………………………………. (b) Explain why the pipe is painted in black. ……………………………………………………………………………………..……… ……... … ………………………………………………………………………………………..… …….. ... [1] (c) Explain why copper is more suitable than plastic for making the pipe in Fig. 4.1. ……………………………………………………………………………………..……… ……... … ………………………………………………………………………………………..… …….. ... [1] 5 An espresso coffee machine injects 0.025 kg of steam at 100 C into a cup of cold coffee of mass 150 g at 20 C. Given: specific heat capacity of the coffee used = 5800 J kg-1 C-1 specific heat capacity of water = 4200 J kg-1 C-1 specific latent heat of vaporisation of water = 2.26 × 106 J kg-1 Determine the final temperature of the coffee. final temperature = …………………….. [ 3] roof pipe containing water hot water out cold water in

7 [Turn over 6 An object is placed in front of a lens L. Fig. 6.1 shows a light ray from the object refracted by L. Fig. 6.1 (a) Determine the image distance. image distance = …………………….. [ 1] (b) Determine the focal length of the lens. focal length = …………………….. [1] L object

8 7 (a) A car stops after travelling some distance. A net charge accumulates on the car tyres due to charging by rubbing (friction) with the road surface and also on the car body due to friction with air. Fig. 7.1 As soon as the driver steps on the ground, he gets a mild electric shock when he touches the metal door of the car as shown in Fig. 7.1. Explain why this happens. ……………………………………………………………………………………..……… ……... … ……………………………………………………………………………………..……… ……... … ………………………………………………………………………………………..… …….. ... [1] (b) The situation in Fig. 7.1 can be prevented by using a suitable material to make the car tyres. Suggest a property that this material must have. ………………………………………………………………………………………..… …….. ... [1]

9 [Turn over 8 An electric cable is made up of 24 thin strands of copper wire, as shown in Fig. 8.1 (not drawn with exact number of strands). Fig. 8.1 Each strand has diameter 0.26 mm. Copper has resistivity of 1.7 × 10−8  m. Calculate (a) the resistance of one strand of wire of length 1.0 m, resistance of wire = …………………….. [ 2] (b) the resistance of the cable of length 5.0 m. resistance of cable = …………………….. [ 2] cable a strand of wire

10 9 An electric oven operates at a voltage of 220 V. It has a heating element with a resistance of 25 . (a) Calculate the rate of energy consumption of the oven. rate of energy consumption = …………………….. [ 2] (b) The cost of 1 kWh of electricity is 28 cents in Singapore. Calculate t