2022 RI Promo Sect A QP

© Raffles Institution [Turn over RAFFLES INSTITUTION 2022 YEAR 5 PROMOTION EXAMINATION 30 September 2022 Time: 2 hr 30 min H2 PHYSICS RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RA FFLES INSTITUTION RAFFLES INSTITUTIO N RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RA FFLES INSTITUTION RAFFLES INSTITUTIO N RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RA FFLES INSTITUTION RAFFLES INSTITUTIO N RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RA FFLES INSTITUTION RAFFLES INSTITUTIO N RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RA FFLES INSTITUTION RAFFLES INSTITUTIO N RAFFLES INSTITUTION RAFFLES INSTITUTION Section A INSTRUCTIONS TO CANDIDATES There are 3 sections in this paper. Section A consists of 15 multiple-choice questions. For eac h question, there are four possible answers A, B, C and D. Choose the one you consider correct and record your choice in soft pencil on the separate Optical Mark Sheet. You are advised to attempt Section A first. The Opti cal Mark Sheets will be collected after the first 30 minutes. Section B consists of 5 structured questions. You are to write your answers in the spaces provided. Section C consists of 1 long structured question and 1 data analysis question. You are to write your answers in the spaces provided. Attempt all questions in Sections A, B and C. There are 9 printed pages, inclusive of the cover page and data & formulae page, in this booklet.

2 © Raffles Institution Data speed of light in free space c  3.00 × 108 m s1 permeability of free space 0  4   107 H m1 permittivity of free space 0  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 × 10 23 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   Formulae uniformly accelerated motion s  21 2ut at 2v  2 2ua s work done on/by a gas W  p V hydrostatic pressure p  ρgh gravitational potential   Gm r temperature T/K  / C 273.15T  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  0 sinx t velocity of particle in s.h.m. v  0 cosvt  22 0x x  electric current I  Anvq resistors in series R  12 RR  resistors in parallel 1/ R  1211 RR  electric potential V  4 Q r alternating current/voltage x  0 sinx t magnetic flux density due to a long straight wire B  0 2 d   I magnetic flux density due to a flat circular coil B  0 2 N r  I magnetic flux density due to a long solenoid B  0n I radioactive decay x   0 expx t decay constant   12ln2 t

3 © Raffles Institution [Turn over 1 The period T of a simple pendulum of length L is given by the following equation 2 LT g where g is the acceleration of free fall. The fractional uncertainty of the period T is 0.020 and that in the measurement of the length L is 0.030. What is the fractional uncertainty of the calculated value of g? A 0.010 B 0.050 C 0.070 D 2.8 2 An equation of the theory of gas flow through small diameter tubes at low pressures is  3 12kr p pQ Lc  where k is a dimensionless constant, r is the radius of the tube, p1 and p2 are the pressures at each end of the tube of length L, c is the speed of the gas molecules What are the base units of Q? A 1 B kg s1 C m3 s1 D m s 3 A baseball at a height of 0.80 m above a flat horizont al ground is projected with a velocity of 12 m s1 at an angle 25° to the horizontal. Air resistance is negligible. What is the horizontal displacement of the ball when it reaches the ground? A 1.5 m B 9.1 m C 11.6 m D 12.8 m

4 © Raffles Institution 4 Two blocks A and B, hang from a light inextensible cord X that passes over a frictionless pulley. A third block C is suspended from block B with a light inextensible cord Y. The masses of blocks B and C are 2.0 kg and 1.0 kg respectively. When the masses are released from rest, they move in the direction of the arrows and the tension in cord Y is 12 N. What is the mass of block A? A 3.2 kg B 3.7 kg C 4.0 kg D 4.7 kg 5 Four forces are applied to a circular object. In which scenario would the object have a non-zero net force but no net torque? A B C D 20 N 20 N 30 N 30 N 20 N 30 N 30 N 20 N 20 N 20 30 N 30 N 20 N 30 N 30 N 20 N pulley A B C X Y

5 © Raffles Institution [Turn over 6 An electric vehicle of mass 1800 kg, travelli ng along a horizontal road at a constant speed of 14 m s1, requires a power of 5.0 kW. What is the required power when the vehicle is moving up a slope of 5.0 at the same constant speed of 14 m s1? A 5.1 kW B 16.5 kW C 26.5 kW D 251 kW 7 A particle moves in a straight line from a point O. The graph shows how its potential energy U varies with its displacement x from point O. Which graph shows how the force F acting on the particle varies with displacement x? A B C D 0 x d 2d 3d U 0 x d 2d 3d F 0 x d 2d 3d F 0 x d 2d 3d F 0 x d 2d 3d F

6 © Raffles Institution 8 A pendulum bob of mass m is attached to a light inextensible string of length L that is fixed to point B. The pendulum bob is released from rest at point A. What is the tension in the string when the pendulum bob is vertically below B? A mg B 1.3 mg C 1.5 mg D 2.0 mg 9 Two stars of masses 3 M and 2 M, orbit in circles about their common centre of mass O, with radii of 2x and 3x respectively. What is the angular speed  of rotation of the stars? A 30.20 GM x B 30.33 GM x C 30.45 GM x D 30.50 GM x 10 A satellite orbits a planet at a distance r from its centre. Its gravitational potential energy is 5.6 MJ. Another identical satellite orbits the planet at a distance 2r from its centre. What is the sum of the kinetic energy and th e gravitational potential energy of this second satellite? A – 0.70 MJ B – 1.4 MJ C – 2.8 MJ D – 11.2 MJ pendulum bob L A B 30° 3M O 3x 2M 2x

7 © Raffles Institution [Turn over 11 A mass undergoes simple harmonic motion with amplitude x0. Which graph shows the variation of the kinetic energy Ek of the mass with its displacement x? A B C D Ek x0 x 0 Ek x0 x 0 Ek x x0 2x0 0 Ek x x0 0

8 © Raffles Institution 12 A spring-mass system is connected to a drivi ng oscillator. The solid curve X on the graph shows how the amplitude of the sp ring-mass system varies with the frequency of the driving oscillator. A certain change in condition causes the response of the system to shift to the dashed curve Y. What is the change in condition? A The mass decreases. B There is less damping. C The amplitude of the driving oscillator increases. D The frequency of the driving oscillator decr