2021 SJI Physics Prelim Year 4 P1

ST JOSEPH’S INSTITUTION PRELIMINARY EXAMINATION 2021 (YEAR 4) CANDIDATE NAME CLASS INDEX NUMBER PHYSICS Paper 1 Multiple Choice Additional Materials: Multiple Choice Answer Sheet 6091/1 27 AUGUST 2021 1 hour (10:30 – 11:30) READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, glue, or correction fluid. Write your name, class and index number in the multiple choice answer sheet. There are forty 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 Multiple Choice 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 on this question paper. The use of an approved scientific calculator is expected, where appropriate. This document consists of 18 printed pages including this cover page.

2 distance / mtime / s0 Going up At maximum height Coming down A -10 m/s2 0 m/s2 +10 m/s2 B -10 m/s2 -10 m/s2 -10 m/s2 C +10 m/s2 +10 m/s2 +10 m/s2 D +10 m/s2 0 m/s2 -10 m/s2 1 Which combination of lengths gives the smallest rectangular area? A 1.0 Gm x 1.0 mm B 1.0 km x 1.0 cm C 1.0 Mm x 1.0 nm D 1.0 μm x 1.0 m 2 A ball is thrown vertically upwards, where it stops momentarily at the maximum height, before falling vertically down. Taking downwards as the positive direction, and ignoring the effects of air resistance, which of the following states its acceleration of its motion? 3 The diagram shows the distance-time graph of a moving object. Which of the following describes this moving object? A It is a ball thrown vertically upwards and falling back to the thrower. B It is a car that starts from rest and speeds up as it moves away from a traffic signal. C It is a rock that is dropped from a high cliff and falling into the sea below.  D It is a train slowing down and coming to a stop at a train station. 4 A gymnast of mass 60 kg lands on a trampoline. If he rebounds upwards with an acceleration of 0.60 m/s2, what is the maximum force exerted by the trampoline on the gymnast? A 36 N B 564 N C 636 N D 672 N

3 5 A parachutist jumps off a plane. After 1.0 min, he opens the parachute and his velocity decreases at a decreasing rate. The following statements are possible explanations why the velocity of the parachutist decreases at a decreasing rate. (I) The velocity decreases as such the air resistance acting on the parachute decreases. (II) The tension exerting on the parachutist decreases. (III) The force of the parachute acting on the air increases. Which of the above statements is/are correct? A (I) only B (I) and (II) only C (II) only D (III) only 6 A container completely filled with water has a mass of 900 g. When it is completely filled with an unknown liquid X, its mass is 865 g. If the weight of the empty container is 2.0 N, what is the density of the unknown liquid, X? Take density of water to be 1000 kg/m3 and gravitational field strength as 10 N/kg. A 0.74 g /cm3 B 0.95 g /cm3 C 1.04 g /cm3 D 1.33 g /cm3 7 A uniform square cardboard of weight 16 N is pivoted freely about a pin fixed at its top left corner to the wall. The square is held at an angle by a force F as shown. What is the value of F? A 4.0 N B 5.7 N C 8.0 N D 11 N

4 XY Zwallvelocity / m/stime / s0Avelocity / m/stime / s0Bvelocity / m/stime / s0Cvelocity / m/stime / s0D 8 A ball is released from rest at X. It rolls down a frictionless slope XY, then across a frictionless horizontal surface YZ. It hits the wall at Z with a sound, and then rolls back up the slope, where it stops momentarily along XY. Which of the velocity-time graphs represents the motion of the ball? 9 A 10 kg object initially at rest is being pulled with a constant force of 8.0 N. The object moves a horizontal distance of 2.0 m and its speed increases to 1.0 m/s. What is the work done against the resistive forces? A 5.5 J B 11 J C 16 J D 21 J

5 10 A piston of mass 4.0 kg is supported by gas trapped in a cylinder. The pressure of the gas is 1.2 × 105 Pa and atmospheric pressure is 1.0 × 105 Pa. The acceleration of free fall is 10 m/s2. What is the area over which the gas exerts a pressure on the piston? A 2.0 10-4 m2 B 2.0 10-3 m2 C 5.0 102 m2 D 8.0 105 m2 11 Diagram P shows a U-tube containing some mercury. The open ends are at atmospheric pressure of 76 cmHg. Diagram Q shows the mercury levels when one of the arms is connected to a gas supply of pressure h cmHg. Which of the following gives the correct height difference in cm between the mercury levels in diagram Q? A h - 76 B ½ (h – 76) C 76 - h D ½ (76 – h)

6 12 The diagram shows a working barometer. Which of the following would not cause the height h of the mercury column to vary? A Adding mercury to the trough. B Change in gravitational field strength. C Change in the temperature. D Leakage of air into the tube. 13 The diagrams show the scale on a voltmeter, connected to a thermocouple thermometer. The probe of the thermocouple is placed in different materials. What is the temperature of the unknown liquid? A 87.5 oC B 113 oC C 120 oC D 125 oC in melting ice in steam in unknown liquid

7 14 A fixed mass of gas is enclosed in a cylinder by a frictionless piston which is free to move. When the temperature of the gas changes, the density of the gas inside the cylinder increases. Which of the following conditions must be true? frequency of collision temperature A decrease decrease B decrease increase C increase decrease D increase increase 15 The diagram below shows a type of ice cream dessert with a sponge cake below it, covered with whipped cream on top. The dessert is placed on a metal tray and the ice cream remains frozen when the entire dish is placed into a hot oven. Which of the following statements about the dessert is correct? A Air is a good conductor of heat and it conducts heat away from the ice cream. B The sponge cake is a good conductor of heat and it conducts heat away from the ice cream to the tray. C The sponge cake is a good insulator and it reduces the transfer of heat from the ice cream to the metal tray. D The whipped cream is a good insulator of heat and this reduces heat gain from the environment.

8 P 16 The diagram shows how the temperature of liquid X and liquid Y changes with time when the same electric heater is used to heat the liquids. If the mass of liquid Y is twice that of liquid X, what is the relationship between the heat capacity of liquid Y, CY to the heat capacity of liquid X, CX? A 4C X = CY B 2CX = CY C CX = 2CY D CX = 4CY 17 80 g of ice at 0°C is added into 500 g of water at 30°C. What is the final temperature of the water? Specific heat capacity of water = 4200 J/kgK. Specific latent heat of fusion of ice = 334 J/g. A 14.9°C B 17.3°C C 20.6°C D 25.9°C 18 The diagram shows the displacement-distance graph of all the particles on a transverse wave on a rope at time t = 0 s. The wave has a frequency of 0.25 Hz. A point P on the rope is marked. The diagram shows the original position of P and four possible new positions of P. What is the position of P at time t = 1.0 s? X Y temperature/°C time/s   2

9 19 The diagram shows crests of circular wavefronts radiating from a point source