YIJC 2024 JC2 PRELIM H2 Phy P3 QP

©YIJC 9749/03/YIJC/24 [Turn over YISHUN INNOVA JUNIOR COLLEGE JC 2 PRELIMINARY EXAMINATION Higher 2 CANDIDATE NAME CG INDEX NO PHYSICS Paper 3 Longer Structured Questions Candidates answer on the Question Paper. No Additional Materials are required. 9749/03 11 September 2024 2 hours READ THESE INSTRUCTIONS FIRST This document consists of 28 printed pages and 4 blank pages. For Examiner’s Use Paper 3 Section A 1 /12 2 /11 3 /7 4 /12 5 /9 6 /9 Section B 7 /20 8 /20 Penalty Paper 3 Total /80 Write your name, class and index number 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, highlighters, glue or correction fluid/tape. The use of an approved scientific calculator is expected, where appropriate. Section A Answer all questions. Section B Answer one question only. The number of marks is given in brackets [ ] at the end of each question or part question.

2 ©YIJC 9749/03/YIJC/24 Data speed of light in free space, c = 3.00  108 m s–1 permeability of free space, o = 4  10–7 H m–1 permittivity of free space, o = 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 ©YIJC 9749/03/YIJC/24 [Turn over Formulae uniformly accelerated motion, s = ut + at2 v2 = u2 + 2as work done on/by a gas, W = p V hydrostatic pressure, p =  g h gravitational potential,  = temperature, T/K = T/°C + 273.15 pressure of an ideal gas, p = mean translational kinetic energy of an ideal gas molecule, E = displacement of particle in s.h.m. x = xo sin  t velocity of particle in s.h.m., v = vo cos  t =   electric current, I = A n v q resistors in series, R = R1 + R2+………. resistors in parallel, = electric potential, V = alternating current/voltage, x = xo sin  t magnetic flux density due to a long straight wire, B = magnetic flux density due to a flat circular coil, B = magnetic flux density due to a long solenoid, B = radioactive decay, x = xo exp(–t) decay constant,  = 2 1  r Gm− 2CV Nm 3 1 kT2 3 )( 22 xxo − R 1 ........11 21 ++ RR r Q o4 dπ2 oIμ r2 No Iμ Ion 2 1t 2 ln

4 ©YIJC 9749/03/YIJC/24 Section A Answer all the questions in the spaces provided. 1 (a) A particular type of slide for children in a theme park is called a ‘drop slide’. This is a slide in which the first part of the fall is vertical. Fig.1.1 shows a child of mass 52 kg on a drop slide. Fig.1.1 (not to scale) The child drops from A, a distance of 2.5 m, before reaching the surface of the slide at B. There is no resistive force from A to B. He then travels down a bend from B to C, while falling a further vertical distance of 5.4 m. At C, the child’s speed is the same as it was at B. After this, the child travels 7.6 m horizontally before stopping at D. (i) Determine the speed of the child at C. speed = ………………… m s−1 [2] (ii) The speed is the same at B and C. Describe the energy changes from A to B to C. ………..…………………………………………………………………………………………… ………..…………………………………………………………………………………………… …………………………………………………………………………………………………. [2] 2.5 m 5.4 m 7.6 m

5 ©YIJC 9749/03/YIJC/24 [Turn over (iii) Calculate the average frictional force slowing the man between C and D. force = ……………… N [2] (b) Fig.1.2 shows a ‘swing ride’ in a carousel, where a man sitting on the rotating swing tilts away from the axis of rotation. Fig. 1.2 (not to scale) (i) Explain why the supporting cable holding the chair tilts as the carousel rotates. ………………………………………………………………………………………….…………. ………………………………………………………………………………………….…………. ………………………………………………………………………………………….…………. …………………………………………………………………………………………………. [2]

6 ©YIJC 9749/03/YIJC/24 (ii) Treat the man and his seat as one entity. Draw and label all the forces acting on it in Fig. 1.3 as the carousel rotates with a constant angular speed. Fig. 1.3 [1] (iii) Calculate the necessary angular speed  for the swings to assume an angle  = 35o with the vertical. angular speed = ……………… rad s−1 [3] [Total: 12]

7 ©YIJC 9749/03/YIJC/24 [Turn over BLANK PAGE

8 ©YIJC 9749/03/YIJC/24 2 (a) State the first law of thermodynamics. ……………………………………………………………………………………………………………. ……………………………………………………………………………………………………………. ………………………………………………………………………………………………………… [1] (b) An ideal gas undergoes a cycle of changes as shown in Fig. 2.1. Fig. 2.1 The gas is initially at point P. It is heated , and its volume increase s at constant pressure to point Q. The gas is allowed to cool at constant volume to R. It then undergoes a compression back to P. (i) For the gas shown in Fig. 2.1, determine 1. the work done on the gas from P to Q. work done = …………………… J [2] pressure / 10 5 Pa volume / cm 3 Q R P 2.79 2.10 950 1125

9 ©YIJC 9749/03/YIJC/24 [Turn over 2. the heat loss to the surrounding from Q to R. heat loss = ………………………. J [3] (ii) There is no heat exchange between the gas and the surrounding when the gas changes from point R to P. Using the first law of thermodynamics, s tate and explain if the temperature increases, decreases or stays the same during the change from point R to P. ……………………………………………………………………………………………………... ……………………………………………………………………………………………………... ……………………………………………………………………………………………………... …………………………………………………………………………………………………. [2] (iii) The molar heat capacity of the gas is the amount of heat supplied to 1 mol of gas to raise its temperature by 1 K. For the transition from P to Q, the molar heat capacity of the gas is 20.8 J mol−1 K−1 and its temperature at P and Q are 350 K and 414 K respectively. Determine the heat supplied to the gas in this transition. heat supplied = ……………………… J [3] [Total: 11]

10 ©YIJC 9749/03/YIJC/24 3 A pendulum consists of a bob (small metal sphere) attached to the end of a piece of string. The other end of the string is attached to a fixed point. The bob oscillates with small oscillations about its equilibrium position, as shown in Fig. 3.1. Fig. 3.1 The length L of the pendulum, measured from the fixed point to the centre of the bob, is 1.24 m. The acceleration a of the bob varies with its displacement x from the equilibrium position as shown in Fig. 3.2. Fig. 3.2 (a) State how Fig. 3.2 shows that the motion of the pendulum is simple harmonic. …………………………………………………….…………………………………………………..….. ……………………………………………………………………………………………………..……... ……………………………………………………………………………………………..………..… [2]