EJC 2019 J1H2 Promo P2 (Printed)

©EJC 2019 9749/02/J1H2PROMO/2019 [Turn over EUNOIA JUNIOR COLLEGE JC1 Promotional Examination 2019 General Certificate of Education Advanced Level Higher 2 CANDIDATE NAME CIVICS GROUP 1 9 - REGISTRATION NUMBER PHYSICS Paper 2 Structured Questions 9749/02 04 October 2019 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 For Examiner’s Use 1 2 3 4 5 6 7 S.F. Total

2 ©EJC 2019 9749/02/J1H2PROMO/2019 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 2019 9749/02/J1H2PROMO/2019 [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, φ = 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 −± ω 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 rπε alternating current/voltage, x = xo sin ωt magnetic flux density due to a long straight wire B = 2 o d µ π I magnetic flux density due to a flat circular coil B = 2 oN r µ I magnetic flux density due to a long solenoid B = onµ I radioactive decay, x = xo exp (–λt) decay constant λ = 1 2 ln2 t

4 ©EJC 2019 9749/02/J1H2PROMO/2019 1 Fig. 1.1 shows a skier of mass 80 kg descending the ramp of a sk i jump and leaving the ramp horizontally. Fig. 1.2 shows a graph of the distance travelled along the ramp against time, from the time the descent starts until the skier leaves the end of the ramp. Fig. 1.1 Fig. 1.2 (a) (i) Using Fig. 1.2, determine the speed at which the skier leaves the ramp. speed = ……….…………......... m s -1 [2] (ii) The skier gains 55% of the available gravitational potential energy as kinetic energy when descending the ramp. Determine the height of the ramp. height = ……….…………......... m [2]

5 ©EJC 2019 9749/02/J1H2PROMO/2019 [Turn over (b) (i) On Fig. 1.3, draw all the forces acting on the skier at that instance. [1] Fig. 1.3 (ii) Hence explain the shape of the graph shown in Fig. 1.2. [2] (c) Assuming that there is no lift or drag due to the air after the skier leaves the ramp , calculate (i) the time for which the skier was in flight, time = ……….…………......... s [1] (ii) the horizontal distance travelled by the skier before landing. distance = ……….…………......... m [1]

6 ©EJC 2019 9749/02/J1H2PROMO/2019 2 (a) (i) Define linear momentum. [1] (ii) State the Principle of Conservation of Momentum. [1] (b) A firework of mass 0.30 kg is launched with an initial velocity v of 8.0 m s-1 at an angle of 60° to the ground, which is horizontal. It explodes at P, the maxim um height of its trajectory. Fig. 2.1 shows the path of the firework from the point of projection O to P. Fig. 2.1 At the instant when the firework is at P, an internal explosion separates it into two parts, X and Y of masses 0.20 kg and 0.10 kg respectively. Immediately after the explosion, X is moves horizontally backwards at 4 m s -1 while Y moves horizontally forward. Assume that the effect of air resistance is neg ligible for the whole process . (i) Show that the speed of Y is 20 m s-1 immediately after the explosion. [2] trajectory

7 ©EJC 2019 9749/02/J1H2PROMO/2019 [Turn over (ii) Calculate the impulse experienced by Y. impulse = .............................. N s [2] (iii) A student estimates that the explosive force acts on Y for 1 ms. Calculate the force acting on Y in this situation. force = ……….…………......... N [2] (c) Determine the energy released in the explosion . energy released = ……….…………......... J [3] (d) On Fig 2 .1, sketch the new path of the firework if air resistance was not negligible. Indicate the top of the trajectory P’ clearly. [1]

8 ©EJC 2019 9749/02/J1H2PROMO/2019 3 An electric hotplate designed to operate on a power supply of 240 V has two coils of wire of resistivity of 9.8 × 10 –7 Ω m. Each coil of wire has a length of 16 m and cross-sectional area 0.20 mm2. (a) For one of the coils, calculate (i) its resistance, and resistance = ……….…………......... Ω [2] (ii) the power dissipated when a 240 V supply is connected across it. power = ……….…………......... W [2] (b) Fig. 3.1 shows how the two coils can be connecte d to operate at different power outputs. Fig. 3.1 Complete Table 3.1 below with either “ON” or “OFF” for each of the switches A, B and C to obtain the lowest and highest levels of operating power without incurring a short circuit. Table 3.1 switch A switch B switch C Lowest Highest [2] 240 V A B C

9 ©EJC 2019 9749/02/J1H2PROMO/2019 [Turn over Blank Page

10 ©EJC 2019 9749/02/J1H2PROMO/2019 4 (a) Explain what is meant by the angular frequency of an oscillation. [1] (b) A thin metal strip is clamped at one end so that it is horizontal. A load of mass M is attached to its free end. The load causes a displacement s of the end of the strip as shown in Fig. 4.1. Fig. 4.1 The load is displaced vertically and then released. The load oscillates. The variation of the displacement s with the acceleration a of the load is shown in Fig. 4.2. Fig. 4.2 (i) Use Fig. 4.2 to determine 1. the displacement of the load before it is made to oscillate, and displacement = ………………………… cm [1] 2. the amplitude of the oscillation of the load. amplitude = ………………………… cm [1]