RI 2021 Y5 H2 Physics CT Sect A QP

© Raffles Institution 9749 RAFFLES INSTITUTION 2021 YEAR 5 TERM 3 COMMON TEST 30 June 2021 Time: 2 hr 30 min H2 PHYSICS RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION RAFFLES INSTITUTION Section A INSTRUCTIONS TO CANDIDATES There are 2 sections in this paper. Section A consists of 15 multiple-choice questions. For each question, four suggested answers are given. You are to choose the most appropriate one and shade your answer on the OMR form, using a soft pencil. You are advised to attempt Section A first. The OMR form will be collected at the end of the first 30 minutes. Section B consists of 7 structured questions. You are to write your answers in the spaces provided. Attempt ALL questions in Sections A and B. This document consists of 10 printed pages.

2 © Raffles Institution 9749 [Turn over Data speed of light in free space c = 3.00 × 108 m s−1 permeability of free space 0µ = 4π × 10−7 H m−1 permittivity of free space 0ε = 8.85 × 10−12 F m−1 = (1/(36π)) × 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 Formulae uniformly accelerated motion s = 21 2ut at+ 2v = 2 2u as+ work done on/by a gas W = pV∆ hydrostatic pressure p = ρgh gravitational potential φ = 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 sinxt ω velocity of particle in s.h.m. v = 0 cosvt ω 22 0xxω= ±− electric current I = Anvq resistors in series R = 12 RR++  resistors in parallel 1/R = 1211 RR++  electric potential V = 4 Q rε0π alternating current/voltage x = 0 sinxt ω magnetic flux density due to a long straight wire B = 0 2 d µ π I magnetic flux density due to a flat circular coil B = 0 2 N r µ I magnetic flux density due to a long solenoid B = 0nµ I radioactive decay x = ( )0 expxt λ− decay constant λ = 12ln2 t

3 © Raffles Institution 9749 [Turn over Section A (15 marks) 1 A ship sails northward with a constant speed v. After some time, it changes its course and sails in the north-west direction with the same speed v. The change in velocity that has taken place in this time interval is A 0.77v in a direction °112.5 anticlockwise from the original direction. B 0.77v in a direction °67.5 clockwise from the original direction. C 1.8v in a direction °22.5 anticlockwise from the original direction. D 1.8v in a direction °157.5 clockwise from the original direction. 2 The diagram shows a regular-sized sugar-glazed donut. Which of the following gives a reasonable estimate for the order of magnitude of the average density of the donut? A −−2310 kg m B −310 kg m C −2310 kg m D −5310 kg m 3 Two stones, X and Y, of different mass es are dropped from the top of a cliff. Stone Y is dropped a short time after stone X. Neglecting air resistance, while the stones are falling, the distance between them will A decrease if the mass of Y is greater than the mass of X. B increase if the mass of Y is greater than the mass of X. C decrease regardless of the masses of X and Y. D increase regardless of the masses of X and Y.

4 © Raffles Institution 9749 [Turn over 4 An object is thrown vertically upwards with an initial velocity and returns to its original position. Which graph incorrectly shows the variation of the quantities of the object’s motion? A B C D 5 A car is travelling with uniform acceleration along a straight road. The road has marker posts every 100 m. When the car passes one post, it has a speed of 10 m s−1 and when it passes the next one, its speed is 20 m s−1. What is the acceleration of the car? A 0.67 m s−2 B 1.5 m s−2 C 2.5 m s−2 D 6.0 m s−2 distance time 0 velocity displacement 0 velocity time 0 displacement time 0

5 © Raffles Institution 9749 [Turn over 6 A 62 kg passenger stands on a weighing scale in an elevator. The graph shows the variation with time t of the velocity v of the passenger when the elevator starts to move upwards at t = 0 s. Which of the following statements is true? A At t = 1.0 s, the reading on the weighing scale is 360 N. B At t = 4.0 s, the reading on the weighing scale is 0 N. C At t = 8.0 s, the reading on the weighing scale is 484 N. D At t = 9.0 s, the reading on the weighing scale is 732 N. 7 Two blocks P and Q of masses 100 g and 900 g respectively, are connected by a light rope strung over a smooth pulley on an inclined plane as shown. The blocks are initially held in place by an external force. Upon removal of the external force, P accelerates upwards while Q accelerates downwards parallel to the plane at 3.0 m s−2. If the inclined plane is frictionless while the frictional force between the surfaces of P and Q is 0.10 N, what is the angle of inclination θ of the plane? A 21° B 22° C 24° D 66° 8.0 2.0 6.0 10.0 0 t / s v / m s−1 Q P

6 © Raffles Institution 9749 [Turn over 8 Two stationary ice-skaters Charlie and Sam, each of mass 60 kg, are directly facing one another on an ice-skating rink. Charlie throws a 1.5 kg medicine ball towards Sam with a horizontal speed of 2.5 m s−1. Sam catches the ball and throws it back to Charlie with the same horizontal speed. The speed of Charlie after catching the ball is A 0.061 m s−1 B 0.063 m s−1 C 0.12 m s−1 D 0.13 m s−1 9 Three identical pails P, Q and R are filled to the brim with water. Three blocks of the same volume, but made of different materials, are placed into the pails. The diagram shows the final positions of the three blocks. Each pail is then separately placed on a weighing scale to determine their weights. How do the weights of P, Q and R compare? A weight of P = weight of Q = weight of R B weight of P = weight of Q < weight of R C weight of P < weight of Q = weight of R D weight of P < weight of Q < weight of R P Q R pail filled with water block

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