EJC 2021 J1 H2 Promo P2 QP

©EJC 2021 9749/02/J1H2Promo/2021 [Turn over EUNOIA JUNIOR COLLEGE JC1 PROMOTIONAL EXAMINATIONS 2021 General Certificate of Education Advanced Level Higher 2 CANDIDATE NAME CIVICS GROUP 2 1 - REGISTRATION NUMBER PHYSICS Paper 2 Structured Questions 9749/02 September/October 2021 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 no blank page. For Examiner’s Use 1 7 2 7 3 10 4 10 5 10 6 10 7 9 8 17 s.f. c.f. Total 80

2 ©EJC 2021 9749/02/J1H2Promo/2021 Data speed of light in free space,    81 71 0 12 1 0 91 19 34 27 31 e 27 p 11 23 1 A 23 1 10 m s 10 H m 10 F m 10 F m 10 C 6 63 10 J s 1 3 00 4 8 85 1 36 1 60 9 11 1 67 66 10 kg 10 kg 10 kg J K mol 6 02 10 8 31 1 38 mol 10 J K c. . / e h. u. m m . . . R. N k . . G                                    11 2 2 2 10 N m kg m 67 81 s 6 9 . g.      permeability of free space, permittivity of free space, elementary charge, the Planck constant, unified atomic mass constant, rest mass of electron, rest mass of proton, molar gas constant, the Avogadro constant, the Boltzmann constant, gravitational constant, acceleration of free fall,

3 ©EJC 2021 9749/02/J1H2Promo/2021 [Turn over Formulae uniformly accelerated motion,     2 22 2 0 0 22 0 12 12 0 0 0 0 0 0 1 2 1 2 2 / K / C 273 15 1 3 3 2 sin cos 1 1 1 4 sin 2 2 exp ln2 at u as V p gh Gm r T T . Nmpc V kT x x t v v t xx R / R / R / R QV r x x t B d NB r s ut v Wp t E Bn t Anvq RR xx                                           I I I I work done on/by a gas, hydrostatic pressure, gravitational potential, temperature, pressure of an ideal gas, mean translational kinetic energy of an ideal gas molecule displacement of particle in s.h.m. velocity of particle in s.h.m. electric current, resistors in series, resistors in parallel, electric potential, alternating current/voltage, magnetic flux density due to a long straight wire magnetic flux density due to a flat circular coil magnetic flux density due to a long solenoid radioactive decay, decay constant

4 ©EJC 2021 9749/02/J1H2Promo/2021 1 A hot air balloon rises vertically at a constant speed of 5.0 m s -1. A stone is dropped from the balloon at time t = 0 s, and takes more than 4.0 s to reach the ground. A second stone is dropped from the hot air balloon at time t = 2.0 s. Air resistance is negligible. (a) On the axes of Fig. 1.1, sketch a graph to show quantitatively how the velocity v of the (i) first stone varies with time from t = 0 s to t = 4.0 s. Label this graph A. [1] (ii) second stone varies with time from t = 2.0 s to t = 4.0 s. Label this graph B. [1] (b) Find the vertical distance between the two stones at t = 4.0 s. vertical distance = …………………………………. m [3] (c) On the same axes of Fig. 1.1, sketch a graph to show how the velocity v of the first stone varies with time from t = 0 s to t = 4.0 s where the effects of air resistance is not negligible. Label this graph C. [2] [Total: 7] Fig. 1.1 t / s v / m s-1 0 2.0 4.0

5 ©EJC 2021 9749/02/J1H2Promo/2021 [Turn over 2 Fig. 2.1 shows the variation with time of the momentum of two colliding lorries A and B. The masses of lorries A and B are 1500 kg and 3000 kg respectively. (a) (i) State the principle of conservation of linear momentum. [1] (ii) On Fig 2.1, draw a line to show the total momentum of the colliding lorries from time t = 0 s to t = 6.0 s. Label the line P. [1] momentum / kN s 0 10 20 30 40 50 1.0 0 2.0 3.0 4.0 5.0 6.0 time / s Fig. 2.1 A B

6 ©EJC 2021 9749/02/J1H2Promo/2021 (b) (i) State Newton’s Second Law of motion. [1] (ii) Determine the magnitude of the force acting on lorry A during the collision. Show your working clearly. force = …………………………………. N [2] (c) By considering the total kinetic energies of the lorries, state and explain the type of collision that the lorries experience. [2] [Total: 7]

7 ©EJC 2021 9749/02/J1H2Promo/2021 [Turn over 3 A uniform ladder of weight W rests in equilibrium against a rough vertical wall, tilted at an angle  from the rough floor. Fig. 3.1 shows a labelled diagram of the ladder, where NG is the normal force on the ladder by the floor and NW is the normal force on the ladder by the wall. (a) State what is meant by the ladder is in equilibrium. [2] (b) Complete Fig. 3.1 to include the friction exerted by the wall fW and the friction exerted by the floor fG. [2] Fig. 3.1 floor wall NG NW W

8 ©EJC 2021 9749/02/J1H2Promo/2021 (c) Show that WG tan 2NN W  [2] (d) The weight of the ladder is 100 N, the angle of tilt is 40 and the normal force acting on the ladder by the floor is 70 N. Find the magnitude of Gf . magnitude of Gf = …………………………………. N [2] (e) The top of the ladder is then coated with a grippy, rubbery material. The ladder is placed back in its original position with the same angle of tilt. State and explain the changes, if any, that will occur to GW and NN . [2] [Total: 10]

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