NYJC 2023 H2 Physics 9749 P1

NYJC 2023 9749/01/J2Prelim/23 [Turn over NANYANG JUNIOR COLLEGE JC 2 PRELIMINARY EXAMINATION Higher 2 CANDIDATE NAME CLASS TUTOR’S NAME CENTRE NUMBER S INDEX NUMBER PHYSICS 9749/01 Paper 1 Multiple Choice 22 September 2023 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, class, Centre number and index number in the spaces at the top of this page. There are thirty questions on 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. Read the instructions on the Answer Sheet very carefully. 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. This document consists of 15 printed pages.

2 NYJC 2023 9749/01/J2Prelim/23 Data speed of light in free space c = 3.00 × 108 m s−1 permeability of free space  = 4 × 10−7 H m−1 permittivity of free space  = 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 /Gm r =− temperature / K / C 273.15TT =  + pressure of an ideal gas 21 3 Nmpc V=   mean translational kinetic energy of an ideal molecule 3 2E kT= displacement of particle in s.h.m. 0 sinx x t = velocity of particle in s.h.m. 0 cosv v t = 22 0xx=  − electric current =I Anvq resistors in series 12 . . .R R R= + + resistors in parallel 121/ 1/ 1/ . . .R R R= + + electric potential 04 QV r= alternating current/voltage 0 sinx x t = magnetic flux density due to a long straight wire  = 0 2 IB d magnetic flux density due to a flat circular coil = 0 2 NIB r magnetic flux density due to a long solenoid = 0B nI radioactive decay 0 exp( )x x t =− decay constant 1 2 ln2 t =

3 NYJC 2023 9749/01/J2Prelim/23 [Turn over 1 A quantity x is measured many times and the number N of measurements giving a value of x is plotted against x. The true value of the quantity is xo. Which graph best represents precise measurements with poor accuracy? A B C D 2 Errors in measurement may be either systematic or random. Which of the following involves random error? A Not allowing for zero error on an analog voltmeter B Not subtracting background count rate when determining the count rate from a radioactive source C Stopping a stopwatch at the end of a race D Using the value of g as 10 N kg-1 when calculating weight from mass 3 Two projectiles, X and Y, are launched into the air from the same place on level ground. They reach the same maximum height as shown. Projectile X is launched vertically upwards and projectile Y is launched at an angle to the horizontal. Air resistance is negligible. Which statement is correct? A X and Y are at rest at their maximum heights. B X and Y are launched with the same speed. C X and Y take the same time to return to the ground. D X and Y travel the same distance. 4 A tractor of mass 1000 kg pulls a trailer of mass 1000 kg via a tow -bar. The total resistance to motion has a constant value of 4000 N. One fifth of this resistance acts on the trai ler. If the maximum breaking force of the tow-bar is 3000N, what is maximum acceleration of the tractor and trailer? A 2.2 m s-2 B 3.0 m s-2 C 3.8 m s-2 D 7.0 m s-2

4 NYJC 2023 9749/01/J2Prelim/23 5 A cylinder of radius r, made of material A and B, is placed on a rough floor as shown. The portion made of material B has a radius of 0. 45r and a density of ρ that is half that of material A . O is the centre of the cylinder and P is t he centre of the portion made of material B. The distance between O and P is 3 r . If the cylinder is entirely made of material A, its weight is 90 N. A force F is applied horizontally to the top of the cylinder so that O and P are at the same height from the floor as shown. What is the force F required to keep the cylinder in this equilibrium position? A 1.5 N B 2.0 N C 4.5 N D 7.5 N 6 Two identical uniform rods, each of weight W, are hinged together to form a structure which is resting on a rough floor as shown. If the reaction forces acting on the structure by the floor are R1 and R2, which of the following shows the forces acting on the structure? F r material A material B rough floor O P

5 NYJC 2023 9749/01/J2Prelim/23 [Turn over 7 A student builds a launcher using an elastic cord of negligible mass and natural length of 1.0 m attached to two rigid supports. Assuming that the elastic cord obeys Hooke’s Law with a spring constant of 80 N m-1 and that the cord is pulled at its midpoint, what is the minimum draw length x needed such that a 200 g water balloon may be propelled with a speed of 10 m s-1? A 0.50 m B 0.56 m C 0.75 m D 1.5 m 8 A simple idea for generating electricity from the tides allows water stored in a container at high tide to flow away through a generator at low tide. At high tide 500 kg of water is stored to a height of 4.0 m. When the valve is opened the container empties in 5.0 s and the generator operates with an efficiency of 40%. What is the average electrical power generated during the period of water flow? A 780 W B 1600 W C 2000 W D 3900 W rigid support rigid support x 1.0 m

6 NYJC 2023 9749/01/J2Prelim/23 9 An aircraft is flying at constant speed in a horizontal circle. Which of the following diagrams best illustrates the forces acting on the aircraft? A B C D 10 A small sphere is travelling horizontally around the circumference of the bigger circular loop in the figure below with an angular velocity of 63.0 rad s-1. The sphere then moves into the smaller loop and continues to move along its circumference. What will be the angular velocity of the sphere when it is moving in the smaller loop? A 37.7 rad s-1 B 63.0 rad s-1 C 105 rad s-1 D 126 rad s-1 19.4 cm 32.4 cm lift weight centripetal force weight centripetal force centripetal force weight lift weight lift

7 NYJC 2023 9749/01/J2Prelim/23 [Turn over 11 A satellite is orbiting the Earth with a radius of 6610 km at a speed of 7780 m s -1. The satellite is boosted to a higher orbit of radius 6890 km. Given that the mass of the Earth is 6.0 × 1024 kg, the speed of the satellite in the new orbit is A 7460 m s-1 B 7620 m s-1 C 7940 m s-1 D 8110 m s-1 12 A small ice cube of mass 20 g is heated and changes from the solid to the liquid state. During this change in state the temperature of the substance does not change. Which statement about this change in state is not correct? A The amount of energy the ice absorbs is equal to the specific latent heat of fusion. B The average kinetic energy of the molecules remains unchanged. C The average pot