RVHS H2 Physics P4 QP

River Valley High School Page 1 of 20 H2 Physics 9749 JC2 Preliminary Examinations 2022 RIVER VALLEY HIGH SCHOOL JC2 PRELIMINARY EXAMINATIONS H2 PHYSICS 9749 PAPER 4 23 AUG 2022 2 HRS 30 MIN CANDIDATE NAME CENTRE NUMBER S INDEX NUMBER CLASS 2 1 J INSTRUCTIONS TO CANDIDATES DO NOT OPEN THIS BOOKLET UNTIL YOU ARE TOLD TO DO SO. Read these notes carefully. Write your name, class and index number above. Candidates answer 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. Give details of the practical shift and laboratory where appropriate in the boxes provided. Write in dark blue or black pen on both sides of the paper. You may use an HB pencil for any diagrams or graphs. Do not use staples, paper clips, glue or correction fluid. Answer all questions. The number of marks is given in brackets [ ] at the end of each question or part question. SHIFT LABORATORY FOR EXAMINERS’ USE 1 / 10 2 / 11 3 / 22 4 / 12 TOTAL / 55 This document consists of 19 printed pages and 1 blank page.

River Valley High School Page 2 of 20 H2 Physics 9749 JC2 Preliminary Examinations 2022 1 This experiment is investigating the current in a circuit. Set up the circuit as shown in Fig. 1.1. The resistor r is used to model the effect of internal resistance in the two batteries. E is the sum of the electromotive force (e.m.f.) of the two batteries. Fig. 1.1 Resistors, each of resistance R, are connected in parallel between P and Q. The current I is measured. The experiment is repeated for different numbers n of resistors between P and Q. It is suggested that I and n are related by the equation REr n =+  I E

River Valley High School Page 3 of 20 H2 Physics 9749 JC2 Preliminary Examinations 2022 (a) (i) Measure the current I for n = 2 and n = 3. Record your measurements in Fig. 1.2. n I / mA 1 n 11 /A − I 2 3 4 70.4 5 81.6 6 87.2 7 95.6 Fig. 1.2 [1] (ii) The values of current for n = 4 to n = 7 are given in Fig. 1.2. Calculate and record the values of 1 n and 11 /A − I in Fig. 1.2. [1] (iii) The absolute uncertainty of the measurement of I can be taken to be ± 2 mA. For your values of I when n = 3, determine the percentage uncertainty of 1 I . percentage uncertainty = ………………………… [2]

River Valley High School Page 4 of 20 H2 Physics 9749 JC2 Preliminary Examinations 2022 (b) When 1 I is plotted against 1 n , determine expressions for the gradient and the y-intercept. gradient = ………………………… y-intercept = ………………………… [1]

River Valley High School Page 5 of 20 H2 Physics 9749 JC2 Preliminary Examinations 2022 (c) (i) Plot a graph of 1 I on the y-axis against 1 n on the x-axis on Fig. 1.3. Fig. 1.3 [1] 11 /A − I 1 n 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50

River Valley High School Page 6 of 20 H2 Physics 9749 JC2 Preliminary Examinations 2022 (ii) Determine values for the gradient and the y-intercept. gradient = ………………………… y-intercept = ………………………… [2] (iii) Use your answer in (b) and (c)(ii) to determine the ratio of R r . R r = ………………………… [1] (iv) Over time, the internal resistance r of the batteries may increase. On Fig. 1.3, draw and label line Z to illustrate what would happen if internal resistance of the batteries increases with their e.m.f. remaining constant. [1] [Total: 10]

River Valley High School Page 7 of 20 H2 Physics 9749 JC2 Preliminary Examinations 2022 BLANK PAGE

River Valley High School Page 8 of 20 H2 Physics 9749 JC2 Preliminary Examinations 2022 2 In this experiment, you will investigate the equilibrium of a metre rule. (a) You have been provided with a metre rule with a string attached to it. Set up the apparatus as shown in Fig. 2.1. Fig. 2.1 Add masses to the mass hanger so that mass m is 80 g. Adjust the pivot so that it is 5 mm from end B of the rule. The distance between the string at end A and the pivot is L. Measure and record L L = ………………………… [1]

River Valley High School Page 9 of 20 H2 Physics 9749 JC2 Preliminary Examinations 2022 (b) Adjust the string loop supporting the 100 g mass so that it is approximately 60 cm from end A. Hold the rule at end A so that the rule is approximately horizontal. Adjust the position of the string loop to find the position where end A is just about to move upwards when the rule is released. The distance between the string at end A and the string loop is y1 as shown in Fig. 2.2. Fig. 2.2 Measure and record y1. y1 = ………………………… Adjust the position of the string loop to find the position where end A is just about to move downwards when the rule is released. The distance between the string at end A and the string loop is y2 Measure and record y2. y2 = ………………………… Calculate y where y = y1 + y2 2 y = ………………………… [1]

River Valley High School Page 10 of 20 H2 Physics 9749 JC2 Preliminary Examinations 2022 (c) Increase m by adding the other masses. Measure the new values of y1 and y2. Repeat until you have five sets of values of m, y1 and y2. Record your results in a table. Include values of y in your table. [4] (d) (i) Plot a graph of y on the y-axis against m on the x-axis. (ii) Draw the straight line of best fit.. (iii) Determine the gradient and y-intercept of this line. gradient = ………………………… y-intercept = ………………………… [5]