RVHS H2 Physics P2 QP

River Valley High School Page 1 of 25 H2 Physics 9749 2023 JC 2 Preliminary Examinations RIVER VALLEY HIGH SCHOOL JC 2 PRELIMINARY EXAMINATIONS H2 PHYSICS 9749 / 2 PAPER 2 13 SEPTEMBER 2023 2 HOURS CANDIDATE NAME CENTRE NUMBER S INDEX NUMBER CLASS 2 2 J INSTRUCTIONS TO CANDIDATES DO NOT OPEN THIS BOOKLET UNTIL YOU ARE TOLD TO DO SO. Read these notes carefully. Write your name, centre number, index number and class in the spaces at the top of this page and on all work you hand in. 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. Candidates answer on the Question Paper. No Additional Materials are required. Answer all questions. The number of marks is given in brackets [ ] at the end of each question or part question. FOR EXAMINERS’ USE Paper 2 1 / 8 2 / 8 3 / 9 4 / 8 5 / 12 6 / 8 7 / 9 8 / 6 9 /12 Deduction Paper 2 / 80 This document consists of 25 printed pages.

River Valley High School Page 2 of 25 H2 Physics 9749 2023 JC 2 Preliminary Examinations Data speed of light in free space, c = 3.00 × 108 m s–1 permeability of free space, µ0 = 4π × 10–7 H m–1 permittivity of free space, ε0 = 8.85 × 10–12 F m–1 = (1/(36π )) × 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

River Valley High School Page 3 of 25 H2 Physics 9749 2023 JC 2 Preliminary Examinations Formulae uniformly accelerated motion 2 2 1 at uts + = 22 2v u as= + work done on / by a gas W pV= ∆ hydrostatic pressure p ghρ= gravitational potential φ = − GM / r temperature T / K = T / °C + 273.15 pressure of an ideal gas > < =2 3 1 cV Nmp mean translational kinetic energy of an ideal gas molecule kT E2 3= displacement of particle in s.h.m., x = x0 sin ωt velocity of particle in s.h.m., v = v0 cos ωt = ) (2 2 0 x x− ±ω electric current, I = Anvq resistors in series, 12RR R=++  resistors in parallel, 121/ 1/ 1/RR R=++  electric potential, r QV 04πε= alternating current/voltage, x = x0 sin ωt magnetic flux density due to a long straight wire, dB π µ 2 0 I= magnetic flux density due to a flat circular coil, r NB 2 0 Iµ= magnetic flux density due to a long solenoid, In B0µ= radioactive decay, x = x0 exp (−λt) decay constant, 2 1 2ln t=λ

River Valley High School Page 4 of 25 H2 Physics 9749 2023 JC 2 Preliminary Examinations Answer all the questions in the space provided. 1 A ball of mass 58 g collide s horizontally with a wall. Fig. 1.1 shows the variation of magnitude of force on the ball F with time. Fig. 1.1 The initial velocity of the ball is 34 m s−1 perpendicular to the wall. The ball rebounded with the same speed and also perpendicular to the wall. (a) Explain what is impulse on the wall. ………………..…………………………………………………………………………… ………………..…………………………………………………………………………… ….…………………………………………………………………………...……… [1] (b) Calculate the change in momentum of the ball. Take initial direction of the ball to be positive. change in momentum = ………………….. kg m s−1 [2] Fmax F / N 2.0 4.0 6.0 t / ms 0

River Valley High School Page 5 of 25 H2 Physics 9749 2023 JC 2 Preliminary Examinations (c) Hence, use Fig. 1.1 to find Fmax on the ball. Fmax = ………………….. N [2] (d) On Fig. 1.2 complete the sketch of the variation of velocity of the ball with time. Fig. 1.2 [3] velocity / m s−1 t / ms 34 0 2 6 4

River Valley High School Page 6 of 25 H2 Physics 9749 2023 JC 2 Preliminary Examinations 2 (a) A cube of volume V contains N molecules of an ideal gas. Each molecule has a component cx of velocity normal to one side S of the cube as shown in Fig. 2.1. Fig. 2.1 The pressure due to one molecule with the component c x of velocity is given by the expression m V cx2 wher e m is the mass of one molecule. Explain how the expression leads to the relation pV = 1 3 Nm< c2 > wher e p is the pressure due to N molecules. …………………..………………………………………………………………………… …………………..………………………………………………………………………… ..………..…………………………………………………………………………… [3] side S cx

River Valley High School Page 7 of 25 H2 Physics 9749 2023 JC 2 Preliminary Examinations (b) Three moles of an ideal gas are in a rigid cubical box with sides of length 0.200 m. (i) Calculate the force that the gas exerts on one side of the box when the gas temperature is 20.0 oC. force = ………………….. N [3] (ii) Kinetic theory of gases assumes that the intermolecular forces between the gas particles are negligible. Suggest and explain how your answer in (b)(i) may change if there are intermolecular forces between particles. …………………..….……………………………………………………………… …………………..….……………………………………………………………… …………………..….……………………………………………………… [2]

River Valley High School Page 8 of 25 H2 Physics 9749 2023 JC 2 Preliminary Examinations 3 One end of a light spring is fixed to a support. A mass is attached to the other end of the spring. The arrangement is shown in Fig. 3.1. Fig. 3.1 This arrangement is used to determine the length l of the spring when mass M is attached to the spring. The procedure is repeated for different values of M. The variation of mass M with length l is shown in Fig. 3.2. Fig. 3.2 M / g l / cm

River Valley High School Page 9 of 25 H2 Physics 9749 2023 JC 2 Preliminary Examinations The spring constant k of the spring is given to be 10.5 N m−1. (a) A mass of 450 g is attached to the spring and is held at rest with length l of 50.0 cm. The mass is then released and the mass oscillates freely. T he angular frequency of the spring-mass system is given by the formula k mω = (i) Calculate the frequency of the system. frequency = …………..………..……..Hz [2] (ii) Using energy considerations , c alculate the speed of the mass during its oscillation when the spring is extended to a length l of 80.0 cm. speed = …………..………..…….. m s−1 [4]

River Valley High School Page 10 of 25 H2 Physics 9749 2023 JC 2 Preliminary Examinations (b) (i) On Fig. 3.3, s ketch the displacement-time curve for the system depicted in (a). Label this curve W. Fig. 3.3 (ii) A student affixed a piece of light cardboard beneath the mass, that extended beyond the perimeter of the mass. Assuming that the spring constant k is unchanged, on the same axes in Fig. 3.3, sketch the displacement-time curve for the mass with cardboard. Label this curve X. [3]