2024 TJC H2 Prelim Paper 1

TEMASEK JUNIOR COLLEGE 2024 JC2 PRELIMINARY EXAMINATION Higher 2 PHYSICS 9749/01 Paper 1 Multiple Choice 12 September 2024 1 hour Additional Materials: Multiple Choice Answer Sheet READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, glue or correction fluid. Write your name and Civics group on the Answer Sheet in the spaces provided. There are thirty questions in this paper. Answer all questions. For each 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 Answer Sheet. Each correct answer will score one mark. A mark will not be deducted for a wrong answer. Any rough working should be done in this booklet. The use of an approved scientific calculator is expected, where appropriate. Do NOT open the booklets until you are told to do so. This booklet consists of 16 printed pages and 2 blank pages.

2 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  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 21 2s ut at=+ 22 2v u as=+ work done on / by a gas W = pV hydrostatic pressure p = gh gravitational potential temperature T/K = T/C + 273.15 pressure of an ideal gas 21 3 Nmpc V= mean translational kinetic energy of an ideal gas molecule 3 2E kT= displacement of particle in s.h.m. velocity of particle in s.h.m. electric current I = Anvq resistors in series R = R1 + R2 + . . . . resistors in parallel 1/R = 1/R1 + 1/R2 + . . . . electric potential V = Q/(40r) alternating current / voltage x = x0 sint 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 x = x0 exp(−t) decay constant Gm r =− 0 sinx x t = 0 cosv v t = 22 0xx=  − 0 2B d  = I 0 2 NB r = I 0Bn = I 1 2 ln 2 t =

3 [Turn Over 1 The speed v of a liquid leaving a tube depends on the change in pressure ∆P and the density 𝜌 the liquid. The speed is given by the equation ()=  nPvk where k is a constant that has no unit. What is the value of n? A 0.5 B 1 C 1.5 D 2 2 A student made a series of measurements of the diameter d, of a wire using four micrometer screw gauges A, B, C and D. The table shows the measurements taken. If the actual diameter of the wire was 1.49 mm, which micrometer screw gauge produced a set of readings that could be described as accurate but not precise? micrometer screw gauge readings d/ mm A 1.49 1.46 1.52 1.50 B 1.48 1.58 1.51 1.40 C 1.35 1.37 1.42 1.42 D 1.32 1.37 1.41 1.50 3 An aircraft flies with airspeed of 350 km h-1 through a 100 km h -1 jet-stream wind from the west. The pilot wishes to fly directly north from an airport in Singapore to an airport Thailand. To achieve this, the pilot points the aircraft away from the north direction. What is the speed of the aircraft in the direction of north relative to the ground? A 250 km h-1 B 335 km h-1 C 364 km h-1 D 450 km h-1

4 4 A double-ended launching device fires two identical steel balls X and Y at exactly the same time. The diagram shows the initial velocities of the balls. They are both launched horizontally, but Y has greater speed. Which statement explains what an observer would see? A X reaches the ground before Y, because X lands nearer to the launcher. B Y reaches the ground before X, because Y has greater initial speed. C Both X and Y reach the ground simultaneously, because gravitational acceleration is the same for both. D Both X and Y reach the ground simultaneously, because air resistance will cause both to have the same final speed. 5 A body of mass 300 g initially at rest is acted on by a force F which varies with time t as shown in the diagram below. What is the speed of the body at the 10th second? A 200 m s−1 B 240 m s−1 C 260 m s−1 D 280 m s−1 force F / N time t / s 0 2 4 6 8 10 12 -12

5 [Turn Over 6 A jet of water of density 1000 kg m -3 leaves the nozzle of a hose of radius 2.0  10-2 m. The water is directed perpendicularly to the wall at a speed of 0.50 m s -1. Assume that the water does not rebound. What is the force exerted on the wall by the water? A 0.314 N B 0.628 N C 1.27 N D 15.7 N 7 Three cuboids with identical dimensions are fully immersed in water as shown. The cuboids are held by strings in identical orientations by strings and in equilibrium at the same depth. Water has density ρ. Cuboid W is made of material of density 4ρ. Cuboid X is made of material of density 2 ρ. Cuboid Y is made of material of density 1.5 ρ. Which statement is correct? A The upthrust on cuboid Y is equal to weight of cuboid Y. B The upthrust on cuboid W is two times the upthrust on cuboid X. C The tension of strings on each cuboid is the same D The tension of string on cuboid W is the greatest. 1.5

6 9 A turntable consists of a rotating horizontal disc moving at a fixed rotational speed. Two small objects P and Q with the same mass, are placed on the turntable as shown, where P is at a distance r1 from the centre O and Q is at a distance r2 from the centre. Which of the following correctly relates P and Q’s linear speeds and their centripetal forces? linear speed centripetal force A same for P and Q greater for Q B same for P and Q greater for P C greater for P greater for Q D greater for P greater for P 8 A wire that obeys Hooke’s law is of length x1 when it is in equilibrium under a tension T1; its length becomes x2 when the tension is increased to T2. What is the extra energy stored in the wire as a result of this process? A ( )( )1212 2 1 xx TT −+ B ( )( )1212 2 1 xx TT −− C ( )( )1212 2 1 xx TT ++ D ( )( )1212 2 1 xx TT +− Turntable rotating on a horizontal plane

7 [Turn Over 10 A cart of mass m goes round a vertical loop of radius r before racing over a hill of radius of curvature 2r as shown in the diagram. If the cart just remains in contact with the track at the top of the loop at point P, what is the force the cart exerts on the track at the top of the hill at point Q? Assume that resistive forces are negligible. A 0 B mg 2 C mg D 3mg 2 11 A stationary object is released from a distance 6R from the surface of the Earth which has radius R and mass M. Which one of the following expressions gives the speed of the object on hitting the Earth? A GM R B 5 GM R C 12 7 GM R D 5 3 GM R 12 A spacecraft orbiting a planet in uniform circular motion has an antenna detached gently from it. Neglecting air resistance, which statement best describes the motion of this detached antenna? A It will move off in a straight line away from the planet. B It will take a parabolic path into the planet. C It will continue to orbit in uniform circular motion. D It will drop straight down into the planet. P Q

8 13 A rigid container has an ideal gas. The mean square speed of the