YEAR 9 PHYSICS TIME: 2 hours

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1 DIRECTORATE FOR QUALITY AND STANDARDS IN EDUCATION Department of Curriculum Management Educational Assessment Unit Track 3 Annual Examinations 2017 YEAR 9 PHYSICS TIME: 2 hours Name: Class: INFORMATION FOR CANDIDATES Where necessary take acceleration due to gravity g to be 10 m/s 2. The use of a calculator is allowed. The number of marks for each question is given in brackets [ ] at the end of each question. You may find these equations useful. Density m = ρ V Pressure P = ρ g h F = P A Forces Moments Energy Heat W = m g Moment = F perpendicular distance P. E. = m g h K. E. = 1 2 mv2 Work Done = F s Work Done = Energy Converted E = P t ΔQ = m c Δθ INSTRUCTIONS TO CANDIDATES Use blue or black ink. Pencil should be used for diagrams only. Read each question carefully and make sure that you know what you have to do before writing your answer. Answer ALL questions. All working must be shown. For Examiner s Use Only Question Max Mark Written 85 Practical 15 This document consists of 11 printed pages. Total 100 Physics Year 9 Track Page 1 of 11

2 SECTION A Each question carries 8 marks. This section carries 40 marks of the total marks for this paper. 1. a) Explain the term non-renewable source of energy. _[1] b) State which of the following sources of energy are renewable and which are non-renewable. Source of Energy Renewable or Non-Renewable Wind Oil Nuclear [3] c) Give ONE advantage and ONE disadvantage of: i) Solar energy Advantage: [1] Disadvantage: [1] ii) Coal: Advantage: [1] Disadvantage: [1] 2. Martina of weight 450 N, stands on her tiptoes as shown in Figure 1. This is a type of lever. The ball of the foot is the pivot, the force in the muscle is the effort E needed to overcome Martina s weight. a) If Martina is in equilibrium calculate the effort E in Martina s muscle. Figure 1 _[2] Page 2 of 11 Physics Year 9 Track

3 b) If Martina had more weight, would she need to make a larger or a smaller effort? Explain. [2] c) A lever can be used to move a large load by exerting a smaller force. Figure 2 below shows such a uniform lever of weight 10 N being used to move a load of 500 N. 1.0 m x 0.5 m F 10 N Figure N i) The total length of the lever is m. [1] ii) The distance x is m. [1] iii) Calculate the size of the smallest value of F needed to move the load. 3. Figure 3 shows two liquids A and B, and a solid C. a) Using the diagram, record and write down the volume of the two liquids A and B, in Table 1. Table 1 Mass (g) Volume (cm 3 ) Density (g/cm 3 ) Liquid A 1.00 Liquid B Solid C [2] A B Figure 3 C b) Name the apparatus needed to find the mass of an object. [1] Physics Year 9 Track Page 3 of 11

4 c) Mention ONE precaution that one must take when reading the volume of a liquid from a thin measuring cylinder. [1] d) Fill in the other missing parts of the table. Use the space below for your working. [2] e) The two liquids are poured in one cylinder. On the diagram of Figure 4, draw and label liquid A and liquid B in their final settling positions. [1] Figure 4 f) Solid C is dropped in the container with the two liquids. Mark the position that the solid will settle in with a C. [1] 4. Table 2 contains information about some of the celestial bodies which orbit the Sun. Table 2 Celestial Object orbiting the Sun Distance from the Sun ( 10 6 km) Time to spin once on its axis (hours) Time to complete orbit around the Sun (years) Mercury Venus Earth Mars Jupiter Pluto a) Which of the celestial bodies in Table 2 has the shortest day and night? _[1] b) Why do you think Mercury takes the shortest time to complete an orbit round the sun? [1] c) Which one of the celestial bodies in the table is NOT considered a planet? Explain. [2] Page 4 of 11 Physics Year 9 Track

5 d) Name the other THREE planets which are not in the table. _[3] e) Explain the meaning of the term light year. _[1] 5. A luggage of mass 18 kg is being loaded by a conveyor belt as shown in Figure 5. luggage B 3 m A conveyor belt Figure 5 a) Calculate the gravitational potential energy of the luggage if it is raised through a height of 3 m. _[2] b) Calculate the power needed to raise the luggage to a height of 3 m in 12 s. [2] c) The actual electrical power supplied is more than the answer obtained in part (b). Explain why this is so. _[1] d) The conveyor belt is removed. The luggage is accidentally dropped from Point B. Calculate the velocity with which the luggage will hit the ground. [3] Physics Year 9 Track Page 5 of 11

6 SECTION B Each question carries 15 marks. This section carries 45 marks of the total marks for this paper. 6. Isaac and Rachela perform an experiment using a helical spring to verify Hooke s Law. a) i) State Hooke s Law. [1] ii) Draw a well labelled diagram of the apparatus they should use in this experiment. Table 3 b) Table 3 show the readings obtained during the experiment. [3] Load/N Length of Spring/mm Extension/mm i) What is the original length of the spring? [1] ii) Work out the extension to complete the table above. [1] iii) Plot a graph of extension on the y-axis against load on the x-axis. [5] iv) Mark the elastic limit with an E on the graph. [1] v) Explain what happens beyond the elastic limit. vi) From your graph find the load needed to make the spring 75 mm long. [1] Page 6 of 11 Physics Year 9 Track

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8 7. Clive decides to go swimming to a beach close to his home. a) i) Calculate Clive s weight if his mass is 72 kg. ii) Clive has different types of sports shoes as shown in Table 4. Which of the following should he choose in order NOT to sink in the sand? Explain your answer. Table 4 A B C D Shoe: [1] Reason: [1] iii) The base area of one foot is 180 cm 2. The area in m 2 is [1] iv) Calculate the pressure produced by Clive when he stands on one foot. b) Clive arrives at the beach and dives into the sea which has a density of 1150 kg/m 3. Calculate: i) the pressure due to the sea water only at a depth of 3 m; Page 8 of 11 Physics Year 9 Track

9 ii) the total pressure at 3 m if the atmospheric pressure is 101 kpa; [2] iii) While Clive is on the sea bed, he breathes out and releases bubbles of air. Explain why the bubbles of air expand as they rise up to the surface. iv) Is it a good idea to go scuba diving and then catch an airplane after a few hours? Explain. [2] 8. James and Sarah swim in a swimming pool which is 15 m long, 10 m wide and 2 m deep. a) i) Find the volume of the water when the pool is full. ii) If the density of the water is 1000 kg/m 3, calculate the mass of the water in the pool. [2] iii) They would like to heat the water from 14 C to 26 C. Calculate the amount of heat energy it would require given that the specific heat capacity of water is 4200 J/ kg C. Physics Year 9 Track Page 9 of 11

10 b) James accidentally drops his swimming robe in the pool. He claims that a wet fleece robe or a dry fleece robe will not make any difference in insulation. Sarah suggests that they do an experiment to see whether this statement is correct. They use the following apparatus to test James idea: two identical jars; kettle with water; pieces of wet and dry fleece; Figure 6 i) Mention TWO other pieces of apparatus that are needed to carry out this experiment. [2] ii) Describe how the experiment can be carried out. [3] Page 10 of 11 Physics Year 9 Track

11 iii) James plotted graphs of temperature against time for both wet and dry fleece. Figure 7 Was James correct to say that there would be no difference in lagging with wet or dry fleece? Explain. iv) Mention TWO ways in which Sarah and James could make sure that the test is fair. END OF PAPER Physics Year 9 Track Page 11 of 11