TJC 2024 H2 Paper 4

TEMASEK JUNIOR COLLEGE 2024 JC2 PRELIMINARY EXAMINATION Higher 2 NAME CG PHYSICS PAPER 4 Candidates answer on the Question Paper. 9749/04 28 August 2024 2 hours 30 minutes READ THESE INSTRUCTIONS FIRST Write your name and C.G. in the spaces provided at the top of this page. Write in dark blue or black pen on both sides of the papers. You may use an HB pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, glue or correction fluid. DO NOT WRITE IN ANY BARCODES. Answer all questions. Write your answers in the spaces provided in this booklet. The use of an approved scientific calculator is expected, where appropriate. You may lose marks if you do not show your working or if you do not use appropriate units. Give details of the practical shift and laboratory where appropriate in the boxes provided. At the end of the examination, fasten all your work securely together. The number of marks is given in brackets [ ] at the end of each question or part question. Shift Laboratory For Examiner’s Use 1 /13 2 / 8 3 /22 4 /12 TOTAL /55 This booklet consists of 19 printed pages and 1 blank page

2 Blank Page

3 1 In this experiment, you will determine the resistivity of two wires with different cross-sectional areas. (a) Measure and record the diameter d1 of wire 1. d1 = ........................................ [1] (b) Calculate the cross-sectional area A1 of wire 1. A1 = ........................................ [1] (c) Repeat (a) and (b) to obtain the diameter and cross-sectional area for wire 2. d2 = ........................................ A2 = ........................................ (d) Connect the circuit shown in Fig. 1.1. The wires should be connected into the circuit using crocodile clips placed close to the ends of the wires. The length of each wire, L between the crocodile clip should be the same at around 35 cm. Fig. 1.1 (e) Close the switch. Adjust the rheostat to obtain a minimum current value I in the ammeter. Record the corresponding V1 and V2 values in the voltmeters. I = …………..……….. V1 = …………..……….. V2 = …………..……….. [2] A V1 V2 Wire 1 Wire 2

4 (f) Adjust the rheostat and obtain at least 6 sets of readings for I, V1 and V2. For each set of readings, the length of each wire L should be constant at approximately 35 cm. [3] (g) Theory suggests that V1, V2 and l are related by the expression I   12 12 11V +V = ρL +AA where  is the resistivity of the wires. Plot a suitable graph to determine the value of .  = …………..…………… [5]

5

6 (h) Using the given apparatus, suggest a way to obtain the ratio of cross -sectional areas of the wires without measuring the diameters of the wires. [1] [Total: 13]

7 2. In this experiment you are provided with a ball attached to a thread and a solid vertical surface. You will investigate how the rebound distance of the ball is related to the release distance when it swings against the solid surface. (a) Assemble the apparatus as shown in Fig. 2.1, with the thread clamped between the two wooden pieces so that L is about 50 cm, and with the wooden block positioned so that it is just touching the stationary ball. Fig 2.1 Measure L. L = ....................................... (b) (i) Pull back the ball and measure the distance a shown in Fig. 2.2. Do not exceed a = 25 cm. a = ....................................... [1] (ii) Release the ball and make measurements to determine the rebound distance b shown in Fig. 2.2. b = ....................................... [2] L wooden pieces vertical wooden block

8 Fig. 2.2 (c) (i) Explain how you ensured that the rebound distance b was measured as accurately as possible. ........................................................................................................................ ........................................................................................................................ ........................................................................................................................ ........................................................................................................................ .................................................................................................................... [1] (ii) Estimate the percentage uncertainty in b. percentage uncertainty in b = ....................................... [1] wooden pieces vertical wooden block

9 (d) For values of a less than 25 cm, theory predicts that 22 22 L L bk L L a −−= −− where k is a constant. Calculate a value for k. k = ....................................... [1] (e) If you were to repeat the experiment in (b), describe the graph that you would plot to determine the value of k. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ............................................................................................................................ [2] [Total: 8 marks]

10 3 In this experiment, you will investigate the behaviour of an oscillating system. You have been provided with a set of acrylic discs and three long strings. (a) (i) Fig. 3.1 shows disc B of diameter D. On the disc are three small holes at equal distance r from the centre of the disc. Fig. 3.1 Measure the diameter D of disc B using a pair of vernier callipers. D = [1] (ii) Measure the distance between the hole and the edge of the disc, d . d = [1] (iii) Using your answers to a(i) and a(ii), determine the distance r. r = [1] D rr r hole hole hole disc B d