EJC 2018 J1H2 Promo P2

©EJC 2018 9749/02/J1H2PROMO/2018 [Turn over EUNOIA JUNIOR COLLEGE JC1 Promotional Examination 2018 General Certificate of Education Advanced Level Higher 2 CANDIDATE NAME CIVICS GROUP 1 8 - REGISTRATION NUMBER PHYSICS Paper 2 Structured Questions 9749/02 02 October 2018 2 hours Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your name, civics group and registration number on all the 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 paper clips, highlighters, glue or correction fluid. The use of an approved scientific calculator is expected where appropriate. Answer all questions. At the end of the examination, fasten all your work securely together. The number of marks is given in brackets [ ] at the end of each question or part question. This document consists of 20 printed pages and 2 blank pages. For Examiner’s Use 1 2 3 4 5 6 S.F. Total 10 10 10 20 20 80 10

2 ©EJC 2018 9749/02/J1H2PROMO/2018 Data speed of light in free space, c = 3.00  108 m s–1 permeability of free space, μo = 4π  10–7 H m–1 permittivity of free space, εo = 8.85  10–12 F m–1 (1/(36 π))  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 ©EJC 2018 9749/02/J1H2PROMO/2018 [Turn over Formulae uniformly accelerated motion, s = ut + ½at2 v2 = u2 + 2as work done on/by a gas, W = pΔV hydrostatic pressure, p = ρgh gravitational potential,  = Gm r temperature, T/K = T / oC + 273.15 pressure of an ideal gas, p = 21 3 Nm cV mean translational kinetic energy of an ideal gas molecule E = 3 2 kT displacement of particle in s.h.m. x = xo sin ωt velocity of particle in s.h.m. v = vo cos ωt =  22 xxo  electric current, I = Anvq resistors in series, R = R1 + R2 + … resistors in parallel, 1/R = 1/R1 + 1/R2 + … electric potential, V = 4 o Q r alternating current/voltage, x = xo sin ωt magnetic flux density due to a long straight wire B = 2 o d   I magnetic flux density due to a flat circular coil B = 2 oN r  I magnetic flux density due to a long solenoid B = on I radioactive decay, x = xo exp (–λt) decay constant λ = 1 2 ln2 t

4 ©EJC 2018 9749/02/J1H2PROMO/2018 1 A ball is thrown from the top of a building at point A with a velocity of 10.8 m s -1, at an angle 40.0° to the horizontal as shown in Fig. 1.1. Fig. 1.1 The ball hits the ground at point B, and the velocity of the ball just before it hits the ground is 60.0° above the horizontal. (a) Determine the horizontal component of the ball’s velocity, ux, at point A. ux = ……………….. m s-1 [1] (b) Show that the vertical component of the ball’s velocity, vy, at point B is 14.3 m s -1, taking downwards as positive. [1] (c) Determine the horizontal distance, x, from the bottom of the building to point B. x = ……………….. m [3] 10.8 m s-1 40.0° A B x

5 ©EJC 2018 9749/02/J1H2PROMO/2018 [Turn over (d) Determine the height, h, of the building. h = ……………….. m [1] At a later time, a rock is thrown horizontally to the right at A such that it also lands at B at the same time as the ball thrown earlier. (e) (i) At what time after throwing the ball is the rock thrown? time = ……………….. s [3] (e) (ii) Determine the speed at which the rock is thrown. speed = ……………….. m s-1 [1]

6 ©EJC 2018 9749/02/J1H2PROMO/2018 2 (a) State the principle of conservation of momentum. [1] (b) A ball B of mass 1.2 kg travelling at constant velocity collides head -on with a stationary ball S of mass 3.6 kg, as shown in Fig. 2.1. Fig. 2.1 The variation with time t of the velocity v of ball B before, during and after colliding with ball S is shown in Fig. 2.2. Fig. 2.2 (i) Using Fig. 2.2, determine the change in momentum of ball B, ΔpB, during the collision. magnitude of ΔpB = …………………….…….…….. kg m s-1 direction of ΔpB = ……………..………………………… [2]

7 ©EJC 2018 9749/02/J1H2PROMO/2018 [Turn over (ii) Calculate the speed of ball S after the collision. speed = ……………….. m s-1 [1] (iii) Complete Fig. 2.2 to show the variation with time of the velocity of ball S before, during and after the collision with ball B. [2] (iv) Determine the force acting on ball S during the collision. magnitude of force = …………………….……..…….. N direction of force = ………………………………… [2] (v) Using your answer in b(ii) and information from Fig. 2.2, deduce quantitatively whether the collision is elastic or inelastic. [2]

8 ©EJC 2018 9749/02/J1H2PROMO/2018 3 A technician placed a block with dimensions 0.20 m × 0.20 m × 0.10 m in a pool of water as shown in Fig. 3.1 . She then measured the depth of immersion h of the block in water. The densities of the block and water are 560 kg m3 and 1000 kg m3 respectively. (a) Calculate the value of h. h = …………………………. m [2] (b) The technician took a 1.0 m long uniform plank of mass 1.5 kg and placed it on the same floating block in Fig. 3.1. When she is standing at 0.010 m from the pivot, the plank becomes horizontal. (i) Draw and name the forces acting on the plank in Fig. 3.2. [3] 0.20 m 0.10 m h Fig. 3.1 0.20 m 0.10 m 0.20 m Fig. 3.2 Edge of the pool Pivot 0.010 m

9 ©EJC 2018 9749/02/J1H2PROMO/2018 [Turn over (ii) Given that the mass of the technician is 40.0 kg, calculate the normal contact force exerted by the block on the plank. Normal contact force = …………………………. N [2] (iii) Determine the new depth of immersion h’ of the block in water, assuming that the block stays upright in the water. h’ = …………………………. m [3]

10 ©EJC 2018 9749/02/J1H2PROMO/2018 4 (a) State the definition of Simple Harmonic Motion. ……………………………………………………………………………………………………. ……………………………………………………………………………………………………. ……………………………………………………………………………………………………. …………………………………………...…………………………………………………..[2] (b) An old motor car travels at steady speed over a rough road on which the height varies in a sinusoidal way. The car’s shock absorber mechanism which normally damps vertical oscillation is not working, and as a result, the car experiences rapid vertical oscillations. Fig. 4 below shows the variation with vertical displacement x from the equilibrium position of the acceleration a, for the vertical motion of the car. Fig. 4 (i) Show that the angular frequency of the vertical oscillation is 8.7 rad s-1. [2] (ii) Hence, or otherwise, calculate the period of the vertical oscillation. period = ………….………… s [1] -0.10 0.10 a / m s-2 x / m 7.6 - 7.6