DHS 2022 Prelim P3

© DHS 2022 9749/03 [Turn over Name: Centre/Index Number: Class: DUNMAN HIGH SCHOOL Preliminary Examination Year 6 H2 PHYSICS Paper 3 Longer Structured Questions Candidates answer on the Question Paper 9749/03 22 September 2022 2 hours READ THESE INSTRUCTIONS FIRST Write your centre number, index number, name and class at the top of this page. 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. Section A Answer all questions. Section B Answer any one question. 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. The number of marks is given in brackets [ ] at the end of each question or part question. For Examiner’s Use Section A 1 4 2 10 3 10 4 9 5 8 6 8 7 11 Section B 8 / 9 20 Total 80 This document consists of 24 printed pages and 2 blank pages.

2 © DHS 2022 9749/03 [Turn over 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 © DHS 2022 9749/03 [Turn over Formulae uniformly accelerated motion, s = ut + at2 v2 = u2 + 2as work done on/by a gas, W = pV hydrostatic pressure, p = gh gravitational potential,  = −Gm/r temperature, T/K = T/oC + 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 = x0 sin t velocity of particle in s.h.m., v = v0 cos t =  electric current, I = Anvq resistors in series, R = R1 + R2 + . . . resistors in parallel, 1/R = 1/R1 + 1/R2 + . . . electric potential, V = alternating current / voltage, x = x0 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 = x0 exp(−t) decay constant,  = 1 2 21 3 Nm cV  kT2 3 22 xxo − r Q o4 0 2 d I  0 2 N r I 0nI 1 2 ln2 t

4 © DHS 2022 9749/03 Section A Answer all the questions in this section in the spaces provided. 1 (a) Make estimates of (i) the mass, in kg, of a wooden metre rule, mass = ……………………. kg [1] (ii) the volume, in cm3, of a tennis ball. volume = ……………………. cm3 [1] (b) The energy E stored in an electrical component is given by 2 2 QE C= where Q is charge and C is a constant. Use this equation to determine the SI base units of C. SI base units of C = ......................................................... [2] [Total: 4]

5 © DHS 2022 9749/03 [Turn over 2 (a) A lump of pure ice floats on pure water in a beaker, as shown in Fig. 2.1. (i) State, qualitatively, the relation between 1. the mass of the ice and the mass of the displaced water, ……………………………………………………………………………………… [1] 2. the density of ice and the density of water. ………………………………………………………………………………………. [1] (ii) A student marks the level of water surface in the beaker and then observes the level as the ice melts. State and explain qualitatively the change, if any, in this level during the melting. Ignore the effects of evaporation. …...…………………………………...…………………………………………………… …...…………………………………...…………………………………………………… …...…………………………………...…………………………………………………… …...…………………………………...…………………………………………………… ………………………………………………………………………………………….. [3] ice water beaker Fig. 2.1

6 © DHS 2022 9749/03 (b) A heavy anchor of volume 0.50 m 3 and density 7800 kg m-3 lies at the bottom of the seabed. A fisherman intends to use a lifting bag to raise the anchor from the seabed. Take the density of sea water to be 1030 kg m-3. (i) Explain what is meant by upthrust. …...………………………………………………………………………………………... ………………………………………………………………………………………….. [1] (ii) Determine the upthrust acting on the anchor. upthrust = ………………………………. N [2] (iii) Determine the volume of air that needs to be released into the lifting bag suddenly in order that the initial acceleration of the anchor is 2.50 m s-2. volume of air = ………………………………. m3 [2] [Total: 10]

7 © DHS 2022 9749/03 [Turn over BLANK PAGE

8 © DHS 2022 9749/03 3 A trolley on a track is attached by springs to fixed blocks X and Y, as shown in Fig. 3.1. The track contains many small holes through which air is blown vertically upwards. This results in the trolley resting on a cushion of air rather than being in direct contact with the track. Fig. 3.1 The trolley is pulled to one side of its equilibrium position and then released so that it oscillates initially with simple harmonic motion. After a short time, the air blower is switched off. The variation with time t of the distance L of the trolley from block X is shown in Fig. 3.2. Fig. 3.2 (a) Use Fig. 3.2 to determine: (i) the initial amplitude of the oscillations, amplitude = ................................................... cm [1]

9 © DHS 2022 9749/03 [Turn over (ii) the angular frequency ω of the oscillations, ω = ................................................... rad s−1 [2] (iii) the maximum speed v0, of the oscillating trolley. v0 = .............................................. cm s−1 [2] (b) Apart from the quantities in (a), describe what may be deduced from Fig. 3.2 about the motion of the trolley between time t = 0 and time t = 24 s. No calculations are required. .……………………………………………………………………………………..……………... .……………………………………………………………………………………..……………... .……………………………………………………………………………………..……………... .……………………………………………………………………………………..……………... .…………………………………………………………………………………..…………….. [3] (c) On Fig. 3.3, sketch the variation with L of the velocity v of the trolley for its first complete oscillation. [2] [Total: 10] Fig. 3.3

10 © DHS 2022 9749/03 4 An arrangement for producing stationary waves in air in a tube that is closed at one end is shown in Fig. 4.1 A loudspeaker produces sound waves of wavelength 0.680 m in the tube. For some values of the length L of the tube, stationary waves are formed. (a) The length L is adjusted between 0.200 m and 1.00 m. (i) Determine the two values of L for which stationary waves are formed. L = …………………… m and …………………… m [2] (ii) On Fig. 4.2, label the positions of all the antinodes with an A and the nodes with an N for the smallest value of L for which a stationary wave is formed. [1] Fig. 4.1 Fig. 4.2