HCI Sample C Paper 2

Name: __________________________________ ( ) Class: _____ HWA CHONG INSTITUTION Sample Paper C PHYSICS Paper 2 Level: Secondary Three Duration: 1 hour 45 mins Do not open this booklet until you are told to do so. INSTRUCTIONS TO CANDIDATES Write your name, index number and class on the top of this page. Answer the questions in Section A and B in the spaces provided. All workings must be shown. In Section B, for Question 10 answer ‘EITHER’ or ‘OR’. INFORMATION FOR CANDIDATES In Sections A and B the intended marks for each question or part of a question are given in brackets [ ]. Any working should be done in the space provided. When necessary, take g to be 10 m s-2 or 10 N kg-1 ___________________________________________________________________________ This question paper consists of 15 printed pages, including this page.

2 SECTION A (40 MARKS) Answer all the questions in this section. 1 The diagram below shows a n oscillating pendulum made from a light in extensible string and a light container filled with water . The length of the pendulum , l, may be determined from the pivot to the centre of the liquid column. Figure 1.1 a) With reference to the positions of Figure 1.1, state what is meant by a complete oscillation. [1] …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… b) Identify a systematic error in this experiment and state a precaution you would take to reduce the effect of the error. [2] …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… c) Suggest what would happen to the period of the oscillation if mercury is used instead of water. [1] …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… l Container of water A B C pivot

3 d) Liquid in the container leaks out as the pendulum is moving. The axes of the graph of the displacement from rest position against time taken is shown below. Sketch a graph to s how the effect of a leaking container by drawing two consecutive oscillations. [2] 2 Figure 2.1 shows a ray of light entering a triangular prism from air. The absolute refractive index of the prism is 1.54 and the speed of light in air is 3.00 X 108 m s -1. Figure 2.1 a) Determine the speed of light in the prism. [2] b) Explain why the light does not bend when it enters the prism. [1] …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… c) Calculate the angle  for the ray of light to travel along the surface of the prism after it exits from P. [2]  Displacement from rest position Time P

4 3 Figure 3.1 shows the position of an object and its image formed through a converging lens. Figure 3.1 a) Draw two principal rays to show how you can determine the focal point, F and the position of the lens, C. Label these points clearly. [3] b) Complete the ray R from the object to the image. [1] c) State how the focal length and the property of the image would change if the original lens is replaced by another lens in which the light ray bends more after passing through it. [2] …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… 4 Figure 4.1 below shows an ordered section of the electromagnetic spectrum. Microwaves P Visible light Q Gamma Rays Figure 4.1 a) Identify the type of EM wave P is and state an application that uses P. [2] …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… b) List one common property between P and Q. [1] …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… object image R

5 c) Describe how absorbing gamma rays affect the cells in the body. [2] …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… 5 A car travels at a constant velocity of 10.0 m s -1 for 10.0 s. Then it accelerates constantly to 15.0 m s-1 in the next 5.0 s. a) Sketch the velocity-time graph over the duration of 15.0 s. [2] b) Calculate the displacement of the car over the duration of 15.0 s. [2] c) A second vehicle, undergoing constant acceleration, started at the same time with the first car and travelled the same distance from rest. It reached the same position as the first car after 15.0s. Calculate the acceleration of the second vehicle. [2]

6 6 A sealed, dark coloured and crumpled, plastic bag containing some gas was put under the sun. After some time, the plastic bag seems to be slightly inflated. a) Using kinetic theory, explain how the behavior of gas molecules in the plastic bag will change over time. [2] …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… b) Describe how the gas molecules exert a pressure on the walls of the plastic bag. [2] …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… c) Explain why the bag under the sun inflates after some time. [2] …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… ……………………………………………………………………………………………………………………………………

7 7 Figure 7.1 shows a cross section of a transverse wave between source P and receptor R. The distance between P and R is 28.0 m. Figure 7.1 a) Calculate the wavelength of the transverse wave. [1] b) Given that it took 3.2 s for the disturbance at P to reach R, calculate the frequency of the wave. [3] c) The source at P was given a disturbance with an amplitude twice the original. How long would it take this new disturbance to reach R? Explain your answer. [2] …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… P R

8 SECTION B (30 MARKS) Answer Question 8, 9 and either 10A or 10B 8 A 100 kg cart rolls down a long incline plane from a vertical height of 2.00 m as shown in Figure 8.1. At the end of the plane is a body of water to bring the cart to a stop . Figure 8.2 is a table of values to show the expected and measured speeds of the cart at the bottom of the plane, just before it enters the body of water, for different values of , the angle of the plane to the horizontal. Figure 8.1 Drop height = 2.00 m  /  Expected Speed/ m s-1 Measured Speed/ m s- 1 Efficiency / % 25.0 6.32 5.70 81.3 30.0 6.32 5.83 85.0 35.0 6.32 5.92 50.0 6.32 6.08 92.4 Figure 8.2 a) State the principle of the conservation of energy. [1] …………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………………………………… b) Show how the expected speed for  = 30.0 is calculated. [2] 2.00 m water 

9 c) Explain, using con cept of work done and conserv ation of energy, how the measured speed is different from the expected speed. [3] …………………………………………………………………………………………………………………………………… …………………………………………………………………………………