EJC 2022 Prelim P2

©EJC 2022 9749/02/J2H2Prelim/2022 [Turn over EUNOIA JUNIOR COLLEGE JC2 PRELIMINARY EXAMINATIONS 2022 General Certificate of Education Advanced Level Higher 2 CANDIDATE NAME CIVICS GROUP 2 1 - REGISTRATION NUMBER PHYSICS Paper 2 Structured Questions 9749/02 August/September 2022 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 staples, paper clips, glue or correction fluid. The use of an approved scientific calculator is expected where appropriate. Answer all questions. The number of marks is given in brackets [ ] at the end of each question or part question. This document consists of 24 printed pages and no blank page. For Examiner’s Use 1 7 2 5 3 8 4 9 5 10 6 8 7 8 8 25 s.f. Total 80

2 ©EJC 2022 9749/02/J2H2Prelim/2022 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 7 10 m s 10 H m 10 F m 10 F m 10 C 6 63 10 J s 1 66 10 kg 10 kg 10 kg J K mol 60 1 2 10 3 00 4 8 85 1 36 60 9 11 0 16 8 31 13 o 8 ml 1 J K c. . / e. . . R. N k. G h. u. m m .    − −− −− −− − − − − − −− − −−      = =   = = = = =  = = = = =  11 2 2 2 10 N m 8 kg m s 6 67 1 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 2022 9749/02/J2H2Prelim/2022 [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 2022 9749/02/J2H2Prelim/2022 1 A uniform metal rod AB of mass 1.2 kg and length 0.40 m is pivoted at end A. End B is suspended by a light spring as shown in Fig. 1.1. The other end of the spring is supported at X. When the rod is in equilibrium, it makes an angle of 30° below the horizontal and lies stationary with the axis of the spring perpendicular to the rod. (a) On Fig. 1.2, draw a labelled diagram showing the forces acting on the rod. Label the forces clearly. [1] A 30° B X spring Y Fig. 1.1 Fig. 1.2

5 ©EJC 2022 9749/02/J2H2Prelim/2022 [Turn over (b) Calculate the tension in the spring. tension = ……………………………… N [2] (c) Determine the magnitude of the reaction force at pivot A. force = ……………………………… N [3] (d) The spring in Fig. 1.1 is now replaced with a spring of larger spring constant and of same natural length. State the change in angle, if any, between the rod and the spring. [1] [Total: 7]

6 ©EJC 2022 9749/02/J2H2Prelim/2022 2 A rubber ball of mass 0.30 kg is positioned directly above a basketball of mass 0.50 kg as shown in Fig. 2.1 The balls are released from a height of 2.0 m from the ground. Assume air resistance is negligible. (a) (i) State the principle of conservation of momentum. [1] (ii) Explain why the principle of conservation of momentum is not applicable to the system of stacked balls. [1] 2.0 m Fig. 2.1 rubber ball basketball

7 ©EJC 2022 9749/02/J2H2Prelim/2022 [Turn over (b) Determine the speed of the stacked balls just before they hit the ground. speed = ……………………………… m s-1 [1] (c) The collision between the balls and ground is elastic. At the instant the basketball loses contact with the rubber ball, it moves with a speed of 3.2 m s-1. The rubber ball is observed to move off at a higher speed than the basketball. Using energy considerations, calculate the speed of the rubber ball as it loses contact with the basketball. speed = ……………………………… m s-1 [2] [Total: 5]

8 ©EJC 2022 9749/02/J2H2Prelim/2022 3 Fig. 3.1 shows two positive point charges q1 and q2 affixed to positions X and Y respectively, on a circular nylon frame centred at point O. The circular frame has a radius r. At point O, the direction of the net electric field strength is directed upwards along OZ. (a) (i) Show that the ratio 1 2 q q is 1.7. [1] (ii) Hence, sketch in Fig. 3.2 the variation of electric field strength with distance along the straight line XY. [2] Fig. 3.1 X 30° 60° Y r nylon frame O Z Fig. 3.2 electric field strength X Y distance

9 ©EJC 2022 9749/02/J2H2Prelim/2022 [Turn over (b) Given that 0 m0 5r.= and 2 200 nC,q = determine the (i) magnitude of electric field strength at O, electric field strength = ……………………………… V m-1 [2] (ii) total electric potential at O, electric potential = ……………………………… V [1] (iii) the work done in moving an additional third charge 32 2q q=− from infinity to point O. work done = ………………………………eV [2] [Total: 8]

10 ©EJC 2022 9749/02/J2H2Prelim/2022 4 (a) Define magnetic flux density. [1] (b) A charged particle is initially located at point P on the plane of the page and is moving to the right with speed v. The charged particle moves within the vicinity of a non-uniform magnetic field that is generated by a long, straight wire carrying current I to the right. The wire is located on the same plane of page as the initial position of the charged particle. As a result, the particle travels along a curved path of non-uniform radius. Fig. 4.1 (i) 1. On Fig. 4.