2012 WSSS MYE with ANS

1 West Spring Secondary School Thirst for Knowledge MID YEAR EXAMINATIONS 2012 PHYSICS 5058 SECONDARY 4 EXPRESS NAME ________________________________ ( ) DATE 09 May 12 CLASS __________ DURATION 2 h 15 min Instructions to Candidates Section A (20 Marks) There are twenty questions in Section A. 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. Section B (50 Marks) and Section C (30 Marks) Answer all questions in the question paper on the spaces provided. The number of marks is given in brackets [ ] at the end of each question or part question. Candidates are reminded that all quantitative answers should include appropriate units. Candidates are advised to show all their working in a clear and orderly manner, as more marks are awarded for sound use of physics than for correct answers. 100 Take g to be 10 m/s2. For Examiner’s Use SETTER: Mr Prakash This document consists of 21 printed pages including this cover page. [ Turn Over ]

2 Section A (20 Marks) 1 A pair of vernier callipers is used to measure the diameter of a boiling tube. Diagram 1 shows the vernier scale when the jaws of the vernier callipers are closed. Diagram 2 shows the vernier scale when the boiling tube is clamped between the jaws of the vernier callipers. What is the correct value of the diameter of the boiling tube? A 1.23 cm B 1.25 cm C 1.27 cm D 1.31 cm 2 The graph shows the speed-time graph of a pendulum bob. What is the period of the oscillation of the pendulum bob? A 0.5 s B 1.0 s C 1.5 s D 2.0 s 3 A helicopter of mass 1000 kg rises vertic ally upwards with a uniform speed of 2 m/s. What is the resultant force exerted on the helicopter as it rises? A 0 N B 500 N C 2000 N D 10000 N 4 A bottle full of water has a mass of 250 g. When the same bottle is filled with liquid X, the mass becomes 160 g. The mass of the empty bottle is 100 g and the density of water is 1.0 g/cm3. What is the density of liquid X? A 0.36 g/cm3 B 0.40 g/cm 3 C 1.07 g/cm 3 D 2.50 g/cm 3 Diagram 1 Diagram 2

3 5 A car of total mass 850 kg slows down from 25 m/s to 12 m/s with a constant deceleration in 5 s. What is the work done against the braking force? A 11 kJ B 110 kJ C 204 kJ D 266 kJ 6 Diagram 1 shows a mercury barometer and diagram 2 shows a mercury manometer placed in the same room. What is the pressure of the gas? A 15 cm Hg B 40 cm Hg C 75 cm Hg D 90 cm Hg 7 The diagram shows a si mple hydraulic jack. Which of the following modification will enable heavier loads to be lifted? Ruler in cm Ruler in cm Diagram 1 Diagram 2

4 8 The diagram shows a barometer which contains mercury and liquid X. The atmospheric pressure is 750 mm Hg and the density of liquid X is 4 3 of the density of mercury. What is the height, h of liquid X? A 110 mm B 150 mm C 200 mm D 250 mm 9 The Brownian motion of smoke par ticles is caused by _____________. A convection currents in the air B collisions between air molecules C collisions betweens smoke particles D collisions between smoke particles and air molecules 10 A gas is heated in a sealed container. Which of the following does not increase? A The average distance between the gas molecules. B The average kinetic energy of the gas molecules. C The number of collisions per second by the gas molecules on the walls of the container. D The force due to the collisions between the gas molecules and the walls of the container. 11 The e.m.f. of a certain thermocouple with one junction X in pure melting ice and the other junction Y in steam is 3.9 mV. With X still in pure melting ice and Y now in a certain boiling liquid, the e.m.f. is -12.7 mV. What would the boiling temperature of the liquid be? A -426°C B -326°C C 326°C D 426°C

5 12 Which of the following statements explains why water is used as a coolant in the radiator of a motor car? A Water is non-volatile. B Water has a high specific heat capacity. C Water is non-corrosive. D Water has a high specific latent heat of vaporisation. 13 Diagram 1 shows a displacement-time graph of a particular wave. Diagram 2 shows a displacement-distance graph of the same wave. What is the speed of the wave? A 0.36 m/s B 0.72 m/s C 2.25 m/s D 9.30 m/s 14 The graph shows a displacement-time graph of a sound wave. What is the frequency of the sound wave? A 2 1000 Hz B 4 1000 Hz C 6 1000 Hz D 2 1 Hz Displacement / mm Displacement / mm 4 4 distance / m time / s 0 6 time / ms Displacement / mm Diagram 1 Diagram 2

6 15 A light ray passes through a triangular glass prism as shown. The refractive index of glass is 1.5. What is the value of angle  ? A 51  B 53  C 61  D 65  16 An object 5.0 cm high is placed 2.0 cm from a converging (convex) lens which is being used as a magnifying glass. The image produced is 6.0 cm from the lens and is 15.0 cm tall. What is the focal length of the lens? A 2.0 cm B 3.0 cm C 4.0 cm D 6.0 cm 17 The table shows the electromagnetic spectrum and the range of frequencies for each electromagnetic wave and rays. A radiation P, has wavelength of 1.0 cm in vacuum, which section of the spectrum is P in? A Radio Waves B Micro Waves C Infra Red rays D Visible light 105 10 6 10 7 10 8 10 9 10 10 10 11 10 12 10 13 10 14 10 15 10 16 10 17 10 18 10 19 10 20 1021 Radio waves Micro waves Visible light Ultra violet rays Gamma rays X rays Infra-red rays Frequency / Hz

7 18 In a Chinese Orchestra performance, a student commented on the sounds of the erhu and the cello. Notes from the erhu are softer and higher pitched than the notes from the cello. Which of the following statements is correct? A Notes from the erhu have higher amplitude and a longer period. B Notes from the erhu have a lower amplitude and a shorter period. C Notes from the cello have a hig her amplitude and a shorter period. D Notes from the cello have a lower amplitude and a longer period. 19 An insulated charged rod R is used to give a perm anent charge to an isolated conducting sphere S by electrostatic induction. What is the required sequence of events? 20 The lengths of two copper wires are in the ratio 1 : 2 and their radii are in the ratio 2 : 1. What is the ratio of their resistances? A 1 : 1 B 1 : 2 C 1 : 4 D 1 : 8 - End of Section A -

8 Section B (50 Marks) 1 Fig. 1.1 shows a cricket ball as it comes into contact with a cricket bat. The cricket ball has a mass of 0.16 kg and it hits the bat with a speed of 25 m/s. After being in contact with the bat for 0.0013 s, the ball rebounds with a speed of 22 m/s in the direction exactly opposite to its original direction. (a) State the difference between speed and velocity. .................................................................................................................................................................... ............................................................................................................................................................... [1] (b) Calculate (i) the change in velocity of the c