DHS 2023 Prelim Physics (Paper 4)

© DHS 2023 9749/04 [Turn over Name: Centre/Index Number: Class: DUNMAN HIGH SCHOOL Preliminary Examination Year 6 H2 PHYSICS Paper 4 Practical Candidates answer on the Question Paper 9749/04 21 August 2023 2 hours 30 minutes READ THESE INSTRUCTIONS FIRST Write your centre number, index number, name and class at the top of this page. Give details of the practical shift and laboratory where appropriate, in the boxes provided. 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. Answer all questions in the spaces provided on the question paper. 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. 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 9 2 12 3 22 4 12 Total 55 This document consists of 19 printed pages and 3 blank pages.

2 © DHS 2023 9749/04 1 In this experiment, you will investigate how the power P dissipated in a resistor varies with the resistance R of the resistor. Set up the circuit shown in Fig. 1.1. Use the 10 Ω resistor for the value of resistance R. (a) (i) Close the switch S. (ii) Measure and record the current I. I = ………………………………. [1] (iii) Open the switch. Fig. 1.1 A S 2 V dry cell 47 Ω R

3 © DHS 2023 9749/04 [Turn over BLANK PAGE

4 © DHS 2023 9749/04 (b) Use the two 10 Ω and three 100 Ω resistors to obtain the value of the resistance R as shown in the Fig.1.2. For each value of R, repeat (a). Also calculate the power dissipated P where P = I2R. R / Ω I / mA P / W 10 20 33 43 50 60 70 100 [4] (c) Plot a graph of P against R. [3] (d) From your graph, state the value of R when P is a maximum. R = ………………………………. [1] [Total: 9] Fig. 1.2

5 © DHS 2023 9749/04 [Turn over

6 © DHS 2023 9749/04 2 In this experiment, you will investigate the movement of a chain of paper clips. (a) (i) You have been provided with a chain of paper clips. Measure and record the mass M of the chain. M = ………………………………. [1] (ii) Using your answer in (a)(i), calculate the mass m of one paper clip. m = ………………………………. [1] (iii) Justify the number of significant figures that you have given for your value of m. …………………………………………………………………………………………….. …………………………………………………………………………………………….. ………………………………………………………………………………………….[1] (b) (i) You have been provided with two identical spheres of modelling clay. Measure and record the mass S of one of the spheres. S = ………………………………. [1] (ii) Calculate c where Sc m= . c = ………………………………. [1]

7 © DHS 2023 9749/04 [Turn over (c) (i) You have been provided with a wooden strip on the bench which is fixed in position. One end of the wooden strip overhangs the bench, as shown in Fig. 2.1. Fig. 2.1 Place the chain on the wooden strip and place one of the spheres on the paper clip at the end of the chain, as shown in Fig. 2.2. The sphere must not touch the wooden strip. Fig. 2.2 Gradually move the paper clips off the end of the wooden strip so that they hang down, as shown in Fig. 2.3. Fig. 2.3

8 © DHS 2023 9749/04 When the chain starts to slip, count and record the number p of paper clips hanging off the end of the wooden strip and the number q of paper clips remaining on the strip. p = ………………………………. q = ………………………………. [2] (ii) Estimate the percentage uncertainty in your value of p. percentage uncertainty = ………………………………. [1] (d) Replace the chain on the wooden strip and place both spheres on the paper clips at the end of the strip, as shown in Fig. 2.4. Fig. 2.4 Determine p and q. p = ………………………………. q = ………………………………. [1]

9 © DHS 2023 9749/04 [Turn over (e) It is suggested that the relationship between p, q and c is p = k (q + nc) where n is the number of spheres on the chain and k is a constant. (i) Using your data, calculate two values of k. first value of k = ………………………………. second value of k = ………………………………. [1] (ii) Explain whether your results support the suggested relationship. …………………………………………………………………………………………….. …………………………………………………………………………………………….. …………………………………………………………………………………………….. ………………………………………………………………………………………… [2] [Total: 12]

10 © DHS 2023 9749/04 3 In this experiment, you will observe the motion of two simple pendulums, and measure the interval between successive times at which the pendulums are moving together. You will investigate how this time interval is affected when the length of one of the pendulums is changed. (a) Set up two pendulums side by side as shown in Fig. 3.1, with each string clamped between two wooden blocks. Set the length of pendulum A to about 0.65 m. Pendulum A should be left at its set length throughout the experiment. Fig. 3.1 (b) (i) Adjust pendulum B so that its length l is about 0.5 m. Measure and record the value of l. l = ………………………………. [1] (ii) Estimate the percentage uncertainty of l. percentage uncertainty = ………………………………. [1]