AISS 2018 Pure Physics Specially Curated School Paper 2 w Ans Set 1

AHMAD IBRAHIM SECONDARY SCHOOL GCE O-LEVEL PRELIMINARY EXAMINATION 2018 PHYSICS PAPER 2 6091/02 Sec 4 Express Date: 14 August 2018 Duration: 1 h 45 min Name: ………………………………………( ) Class: …………… READ THESE INSTRUCTIONS FIRST Do not open this booklet until you are told to do so. Write down your name, class and register number on this page and on any additional writing papers. Write in dark blue or black pen. You may use an HB pencil for any diagrams, graphs, tables or rough working. Do not use staples, paper clips, glue or correction fluid. Section A Answer all questions. Section B Answer all questions. Question 12 has a choice of parts to answer. Information for candidates: Candidates are reminded that all quantitative answers should include appropriate units. The use of an approved scientific calculator is expected, where appropriate. 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. The number of marks is given in brackets [ ] at the end of each question or part question. This question paper consists of 19 printed pages FOR EXAMINER’S USE Section A / 50 Section B / 30 TOTAL / 80

2 Section A Answer all the questions in this section. 1 A rubber ball is dropped freely from a height of 20 m. The ball hits the ground at time t and rebounds vertically upwards with half its maximum velocity. The maximum velocity of the ball just before it hits the ground for the first time is V. (a) In the axes below, sketch the velocity-time graph of the ball from the point of release to the time when it has rebounded to its new maximum height. (Ignore air resistance) [2] (b) Using information from the graph, determine the velocity of the ball just before it hits the ground for the first time. velocity = ………………………………. [2] (c) Find the displacement of the ball after it has rebounded to its maximum height. displacement = ………………………………. [2] (d) State the change in velocity of the ball during its rebound. change in velocity = ………………………………. [1]

3 2 Fig. 2.1 shows three cylinders X, Y and Z are supported by three ropes that passes through ring R. Fig. 2.1 Ring R is in equilibrium under the action of three forces Fx, Fy and Fz. Draw a vector diagram to find Fx and angle . Fx = ………………………………. angle θ = ……………………….. [4] q

4 3 A uniform rod AB of length 3 m weighs 10 N. It is suspended by two identical strings at points X and Y as shown in Fig. 3.1. T1 and T2 are the tension in the strings. Fig. 3.1 Two weights, 20 N and P, are hung from the rod at point A and 1.6 m from X respectively. (a) Draw the weight of the rod in Fig. 3.1 and label it W. Indicate clearly its distance from point A. [1] (b) Determine T2, the tension of the string at Y. T2 = ………………………………. [2] (c) Hence, or otherwise, determine T1, the tension of the string at X. T1 = ………………………………. [1] 20 N X Y A B T1 T2 String String 2.3 m 1.6 m 0.5 m 0.2 m P 40 N

5 4 A small jet plane which can carry six people is shown in Fig. 4.1. Fig. 4.1 The mass of the fully-loaded jet plane is 2560 kg. It is initially at rest. When the jet plane is taking off, the two jet engines can exert a total thrust force of 8000 N and the friction between the wheels and the ground is 340 N. Both forces remain constant at these values during take-off. (a) Calculate the acceleration of the plane as it starts to move. acceleration = ………………………………. [2] (b) Explain what happens to this acceleration as the jet plane speeds up. …………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………….... [2] (c) The average acceleration during take-off is 2.2 m/s2. (i) Calculate the time that the jet plane will take to reach a take-off speed of 55 m/s. time = ………………………………. [1] (ii) Determine the minimum length of the runway that is required for the jet plane to take off. minimum length = ………………………………. [2]

6 (d) Suggest why the wheels of the jet plane are folded into the body of the jet plane after take-off. ………………………………………………………………………………………………………………………………………………………………………………………………………… [1] 5 Fig. 5.1 below shows a long vertical glass tube with one end immersed in mercury and the other connected to a vacuum pump at A. The tube fits tightly into a bell jar. With an opening at B and all air in the glass tube pumped out via A, the mercury rises to a maximum height of 76.0 cm above the dish. Fig. 5.1 (a) Explain why the mercury only can rise to a maximum height of 76.0 cm. …………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………….... [2] (b) If the density of mercury is 13600 kg/m3, calculate the pressure at Y in pascals. pressure = ………………………………. [2] to vacuum pump glass tube 100 cm long mercury 76.0 cm A B Y

7 (c) A container of air initially at atmospheric pressure is connected to B and heated over a flame as shown in Fig. 5.2. Fig. 5.2 Using kinetic theory of matter, explain whether the height of mercury column rises, falls or remains the same. …………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………….... ………………………………………………………………………………………………….... [3] 6 John conducts an experiment to determine the specific latent heat of vaporisation of water. He places an immersion heater fully immersed in water in an open steel container. The voltage across the immersion heater is 240 V and the current which passes through the heating element is 1.6 A. John measures the mass of water after steady boiling is achieved, and again after another 8 minutes. He discovers that the mass of water in the container decreases by 0.075 kg during the 8 minutes. (a) Calculate the specific latent heat of vaporisation of water. specific latent heat of vaporisation = ………………………………. [2] A to vacuum pump 76.0 cm mercury flame container B

8 (b) Is the value calculated in (a) higher than the actual specific latent heat of vaporization of water? Explain why. ………………………………………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………… [2] (c) John’s friend Ali comments that it is better to use a vacuum flask to contain water rather than a steel container. Explain why this is so. ………………………………………………………………………………………………………………………………………………………………………………………………………… [1] 7 A collector views a postage stamp of height 1.5 cm through a lens. The lens is 2.0 cm from the stamp and the ratio of height of image to height of object is 3.0. (a) In Fig. 7.1, complete the full scale ray diagram to determine the image of the stamp [3] (b) State what is meant by a virtual image. ………………………………………………………………………………………………………………………………………………………………………………………………………… [1] position of the lens 2.0 cm image viewed from this side of the lens Fig. 7.1 ray A principal axis

9 (c) Use your drawing to determine the focal length of the lens. focal length = ………………………………. [1] (d) On Fig. 7.1, complete the path of ray A after passing through the lens. [1] 8 (a) An acetate rod held in the hand may be charged positively by rubbing it with a cloth, but a copper rod held in the hand cannot be charged this way. (i) Explain how the acetate rod acquires positive charges when rub with a cloth. …………………………………………………………………………………………………………………………………………………………………………………………………………………………………