2023 ASRJC H2 Physics Promo P2 Final

1 9749/02/ASRJC/2023PROMO [Turn over Name: _____________________________ ( ) Class: 24 / ______ 2023 JC1 Promotional Exam PHYSICS Higher 2 9749/02 Paper 2 Structured Questions Tuesday 26 September 2023 2 hours Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your name, class index number and class in the spaces at the top of this page. 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. The use of an approved scientific calculator is expected, where appropriate. Answer all questions. The number of marks is given in brackets [ ] at the end of each question or part question. This document consists of 24 printed pages and 0 blank page. For Examiner’s Use Paper 1 (20 marks) Paper 2 (80 marks) 1 2 3 4 5 6 7 8 9 Deductions Total ANDERSON SERANGOON JUNIOR COLLEGE

2 9749/02/ASRJC/2023PROMO Data speed of light in free space c = 3.00  108 m s−1 permeability of free space 0 = 4  10−7 H m−1 permittivity of free space 0 = 8.85  10−12 F m−1 (1/(36))  10−9 F m−1 elementary charge e = 1.60  10−19 C the Planck constant h = 6.63  10−34 J s unified atomic mass constant u = 1.66  10−27 kg rest mass of electron me = 9.11  10−31 kg rest mass of proton mp = 1.67  10−27 kg molar gas constant R = 8.31 J K−1 mol−1 the Avogadro constant NA = 6.02  1023 mol−1 the Boltzmann constant k = 1.38  10−23 J K−1 gravitational constant G = 6.67  10−11 N m2 kg−2 acceleration of free fall g = 9.81 m s−2

3 9749/02/ASRJC/2023PROMO [Turn over Formulae uniformly accelerated motion =s 2 2 1 atut + =2v asu 22 + work done on/by a gas =W Vp hydrostatic pressure =p gh gravitational potential = r Gm− temperature T/K = T/C + 273.15 pressure of an ideal gas p =  2 3 1 cV Nm mean translational kinetic energy of an ideal gas molecule =E kT2 3 displacement of particle in s.h.m. x = x0 sin  t velocity of particle in s.h.m. v = v0 cos  t = 22 xxo − electric current I = Anvq resistors in series R = R1 + R2 + … resistors in parallel 1/R = 1/R1 + 1/R2 + … electric potential V = r Q o4 alternating current/voltage x = x0 sin  t magnetic flux density due to a long straight wire B = d o   2 I magnetic flux density due to a flat circular coil B = r No 2 I magnetic flux density due to a long solenoid B = Ino radioactive decay x = x0 exp(–t) decay constant  = 2 1 2ln t

4 9749/02/ASRJC/2023PROMO Answer all the questions in the spaces provided. 1 A child of weight 330 N is at a point X at the top of a slide. The slide is at the edge of a swimming pool, as shown in Fig. 1.1. Fig. 1.1 (not to scale) The child moves from rest to the lowest point of the slide that is a vertical distance of 4.0 m below X. The child continues moving towards point Y which is at the end of the slide and a vertical distance of 1.1 m above the lowest point. The kinetic energy of the child at Y is 540 J. (a) An average frictional force of 52 N acts on the child when moving from X to Y. By considering changes of energy, determine the distance moved by the child from X to Y. distance moved = …………………………….m [2] (b) The child leaves the slide at point Y with a velocity that is at an angle of 41 o to the horizontal. The path of the child through the air is shown in Fig. 1.2. Fig. 1.2 (not to scale)

5 9749/02/ASRJC/2023PROMO [Turn Over (i) Calculate the speed of the child at point Y. speed = …………………………….m s−1 [1] (ii) Show that the speed at point Z is 4.3 m s−1. [1] (iii) At point P, along the path of the child, the child is moving at an angle of 48 o to the horizontal. Air resistance is negligible. For the child at point P, determine the vertical distance through which he has fallen from Y. vertical distance = ……………………m [3]

6 9749/02/ASRJC/2023PROMO (iv) On Fig. 1.3, sketch the variation of the kinetic energy of the child with his vertical height above point Y for the movement of the child from Y to Z. Numerical values are not required. [1] (c) Use energy considerations to suggest why, if the child causes a large splash on hitting the swimming pool, he will be slowed down in a shorter distance than when no splash is produced. …………………………………………………………………………………............................. …………………………………………………………………………………………….……….. ………………………………………………………………………………………….………….. …………………………………………………………………………………………….......... [2] [Total: 10] h height kinetic energy 0 0 Fig. 1.3

7 9749/02/ASRJC/2023PROMO [Turn Over 2 Two particles A and B, each of mass m, collide elastically, as illustrated in Fig. 2.1. Fig. 2.1 The initial velocity of A is 500 m s−1 in the x-direction and B is at rest. The velocity of A after collision is vA at 60° to the x-direction. The velocity of B after the collision is vB at 30° to the x-direction. (a) (i) State an expression in terms of m, for the total initial momentum of A and B. ……………………………………………………………………………….…………....[1] (ii) State an expression in terms of m, vA and vB for the total momentum of A and B after the collision 1. in the x-direction, …………………………………………………………………………………............. 2. in the y-direction. …………………………………………………………………………………............. [2]

8 9749/02/ASRJC/2023PROMO (iii) By considering the components of momentum in the x and y directions, show that the magnitude of the final velocity of A, vA is 250 m s−1. [2] (b) Determine the magnitude and direction of the change in velocity of A with a diagram indicating the direction of the change in velocity. magnitude of change in velocity = …………………………….. m s−1 [2] direction of change in velocity = …………………………………[1] [Total: 8]

9 9749/02/ASRJC/2023PROMO [Turn Over 3 (a) A hollow plastic sphere is attached at one end of a bar. The sphere is partially submerged in water and the bar is attached to a fixed vertical support by a pivot P, as shown in Fig. 3.1. The sphere has weight 0.30 N. The distance from P to the centre of gravity of the sphere is 0.29 m. Assume that the weight of the bar is negligible. Calculate the moment of the weight of the sphere about P. moment = …………………………….N m [2]

10 9749/02/ASRJC/2023PROMO (b) The system shown in Fig. 3.1 is part of a mechanism that controls the amount of water in a tank. Water enters the tank and causes the sphere to rise. This results in the bar becoming horizontal. Fig. 3.2 shows the system in its new position. In this position the rod R exerts a force to compress a horizontal spring that controls the water supply