FORM 5 PHYSICS TIME: 2 hours

Size: px

Start display at page:

Download "FORM 5 PHYSICS TIME: 2 hours"

Shon Singleton
6 years ago
Views:

1 DIRECTORATE FOR QUALITY AND STANDARDS IN EDUCATION Department of Curriculum Management Educational Assessment Unit Annual Examinations for Secondary Schools 2017 Track 3 FORM 5 PHYSICS TIME: 2 hours Name: Answer ALL questions in the spaces provided on the Examination Paper. All working must be shown. The use of a calculator is allowed. Where necessary take the acceleration due to gravity g = 10 m/s 2. Density m = ρ V Pressure P = ρ g h F = P A Class: Moments Energy Moment = F perpendicular distance PE = m g h KE = 1 2 mv2 Work Done = F s Work Done = Energy Converted E = P t Force F = m a W = m g Motion Electricity total distance (u + v) t Average Speed = total time s = s = ut at2 v = u + at v 2 = u 2 + 2as Momentum = m v Q = I t V = I R E = Q V P = I V R L/A E = I V t R T = R 1 + R 2 + R 3 1 R T = 1 R R 2 Electromagnetism Heat Waves Radioactivity N 1 N 2 = V 1 V 2 ΔQ = m c Δθ real depth η = apparent depth v = f λ f = 1 T A = Z + N η = the speed of light in air the speed of light in medium m = h i image distance = h o object distance Marks Grid: For the Examiners use ONLY Question Th. Prac Total Final Mark Mark Score Physics Form 5 Secondary Track Page 1 of 14

2 Section A: This section has 7 questions. Each question carries 10 marks (70 marks). 1. A student hangs an iron block to a stand and clamp as shown in Figure 1. a) Name the apparatus X that is used to measure X the weight of the iron block. 12 N [1] b) Draw and label the forces acting on the iron bar in Figure 1 (a). [2] c) The student lowers the iron block in a measuring cylinder as in Figure 1 (b). The liquid in the measuring cylinder rises from 50 cm 3 to (a) Figure 1 (b) 203 cm 3. i) Calculate the volume of the iron block. ii) Calculate the mass of the iron block in grams and hence determine the density of the iron block. [3] iii) The student replaces the liquid in the measuring cylinder with one that has a higher density. Will this affect the density of the iron block? Explain your answer. 2. Nicole uses a computer simulation to determine the weight of steel blocks with different masses on the moon. She presents the data as shown in the graph of Figure 2. a) Weight is a vector quantity. Define a vector quantity. [2] b) Nicole reads off the weight of the 3 kg mass wrongly. Use the graph to find the correct value of the weight of the 3 kg mass. [1] Figure 2 Page 2 of 14 Physics Form 5 Secondary Track

3 c) Determine the acceleration due to the gravity on the moon by finding the gradient of the graph. [3] d) What is the relationship between the weight W and the mass m? Give a reason for your answer. [2] e) Nicole repeats the same simulation using the Earth s gravitational acceleration. On the same graph of Figure 2, sketch the new line graph that she obtains. [2] Plutonium-242 (Pu-242) is a silvery radioactive solid. The symbol for plutonium-242 nucleus is 94Pu. a) i) Underline: When radioactive decay occurs, a nucleus which is (unstable, stable, unchanging) decays to a more stable nucleus by emitting radiation. [1] ii) The proton number Z of Pu-242 is. [1] iii) Calculate the neutron number N of Pu [1] b) Table 1 shows the properties of the three types of radiation. Complete the table, by filling in the type of radiation. Nature Electromagnetic wave Particle Particle Nucleon Number A none 0 4 Proton Number Z none -1 2 Type of Radiation c) The activity of a sample of Iodine-131 drops from 8000 counts per minute to 500 count per minute in 32 days. Calculate the half-life of the sample of iodine. [4] [3] 4. Two metal conducting spheres L and M are on insulating stands. L and M are positively charged. a) What is the difference between conducting and insulating materials? L M (a) L M [2] (b) Figure 3 Physics Form 5 Secondary Track Page 3 of 14

4 b) The charge on sphere L is C while that on sphere M is C. The spheres are placed in contact with each other. What is the net final charge on both spheres? [3] c) The spheres are earthed by touching them (see Figure 3 b). The net charge found in part (b) flows between the spheres and earth in 0.01 s. Calculate the current flow. [3] d) Explain, in terms of the movement of electrons, what happens to the charge on the spheres when they are earthed. [2] 5. Johnny is splitting wooden logs for the stove. He uses the setup shown in Figure 4. The total mass of the blade and the rod is 3 kg. a) The contact area between the blade and the log is m 2. Calculate the pressure exerted by the rod and blade on the log. [3] b) Johnny adds a sliding mass to the rod. He releases the mass and it hits the blade, exerting an extra force of 80 N. Calculate the maximum pressure exerted by the system. Figure 4 [4] c) Without changing the blade, state TWO ways how Johnny can increase the pressure exerted on the log. [2] d) After several uses, the blade becomes blunt (less sharp). How will this affect the pressure exerted by the blade? [1] Page 4 of 14 Physics Form 5 Secondary Track

5 6. Figure 5 shows a bar magnet being pulled out of the solenoid. N S C D Figure 5 a) i) Underline: In electromagnetic induction, (Faraday s, Lenz s, Snell s) law states that when the rate of cutting of magnetic flux increases, the induced current flowing through the solenoid increases. [1] ii) The magnet is pulled away from the solenoid. State the magnetic pole that is induced at end C of the solenoid. iii) In which direction will the needle on the galvanometer deflect as the magnet is pulled away from the solenoid? b) Part AB of the graph in Figure 6 shows how the current changes as the magnet is moved inside the solenoid. i) Which section of the graph shows that the magnet stopped moving inside the solenoid? Explain. A B C D [3] ii) State what is observed on the galvanometer during section CD of the graph. Explain. Figure 6 iii) The same procedure is repeated using a weaker magnet. On the same graph, sketch a curve that represents the induced current by this weaker magnet. [2] Physics Form 5 Secondary Track Page 5 of 14

6 7. An asteroid is orbiting the Sun as shown in Figure 7. a) In which of the positions, A, B, C or D is the effect of the Sun s gravity on this asteroid greatest? Explain. [2] Figure 7 b) The table below gives information about three of the planets in our solar system. Planet Average distance from sun (millions of km) Time for one orbit (Earth years) Average surface temperature ( C) Venus Mars Neptune i) Use information in the above table to help you explain how the surface temperature of these planets varies with distance from the Sun. ii) Calculate how many days there are in ONE year on Mars. iii) Calculate the time taken for light rays from the Sun to reach planet Neptune if the speed of light is m/s. iv) Name ONE benefit of space exploration. v) Name ONE unanswered question about the universe. Page 6 of 14 Physics Form 5 Secondary Track

7 Section B. This section has 5 questions. Each question carries 20 marks (100 marks). 8. This question is about light and its properties. a) Light is an electromagnetic wave. Name TWO properties common to all electromagnetic waves. [2] b) An archer fish is able to prey on insects by shooting a jet of water from its mouth. i) On Figure 8, draw an arrow to indicate the direction of the ray of light that enables the fish to see the insect. [1] air water ii) Mark with an x the position where the fish sees the image of the insect. [1] Figure 8 iii) Name the phenomenon which causes the light to bend as it changes medium. iv) If the critical angle for water is exceeded, the fish is not able to see the insect at all. Explain. c) Britney investigates the relationship between the object distance and image distance of a convex lens as shown in Figure 9. She tabulates her results. illuminated object object distance lens image distance screen Figure 9 Object distance (cm) Image distance (cm) i) Describe briefly how she carries out the experiment. [3] ii) Plot a graph of image distance (cm) on the y-axis against object distance (cm) on the x-axis. Draw the best fit curve through your points. [5] Physics Form 5 Secondary Track Page 7 of 14

8 Page 8 of 14 Physics Form 5 Secondary Track

9 d) A convex lens has a focal length of 2 cm. An object of height 1.6 cm is placed 3 cm away from the centre of the lens. i) Draw a ray diagram to scale to show how the image forms. [3] lens ii) State ONE characteristic of the image formed. iii) Calculate the magnification of the lens. 9. This question is about electromagnetism and its applications. a) Draw the magnetic field pattern for each of the following diagrams. cardboard copper wire solenoid (i) (ii) [2] [3] Physics Form 5 Secondary Track Page 9 of 14

b) Mark is supplied with three identical rods made of different metals: aluminium, steel and iron. He wants to construct an electromagnet. Explain why neither aluminium nor steel can be used.

ii) On Figure 10, draw an arrow to show the direction in which the copper rod rolls. [1] iii) Name the rule used to find the direction in which the rod rolls.

10 b) Mark is supplied with three identical rods made of different metals: aluminium, steel and iron. He wants to construct an electromagnet. Explain why neither aluminium nor steel can be used. [2] c) When the switch is closed, the copper rod shown in Figure 10 starts rolling. powerful magnet copper rod aluminium rod switch battery Figure 10 i) State why the copper rod starts to roll. ii) On Figure 10, draw an arrow to show the direction in which the copper rod rolls. [1] iii) Name the rule used to find the direction in which the rod rolls. iv) State ONE way through which the copper rod can be made to roll faster. v) Name a suitable application for the effect observed in Figure 10. d) A device called a solenoid valve is represented in Figure 11. The iron rod, plunger and plug are connected together and can move vertically upwards or downwards. i) Explain why water can flow when the switch is closed. iron rod coil switch d.c. supply + - plug spring (fixed) water out hole plunger water in [4] Figure 11 Page 10 of 14 Physics Form 5 Secondary Track

ii) Explain the function of the spring while the circuit is switched off. iii) The current flowing through the coil is reversed. Does the device work? Explain. 10.

11 ii) Explain the function of the spring while the circuit is switched off. iii) The current flowing through the coil is reversed. Does the device work? Explain. 10. This question is about energy and motion. a) Paul wants to join the army. His agility skills are tested by climbing a flight of steps in the shortest time possible. His mass is 60 kg and he climbs 10 steps in 2.5 seconds. Each step is 15 cm high. i) Calculate the total height of the steps in metres. ii) Calculate the gravitational potential energy gained when he reaches the tenth step. iii) Calculate his power. iv) Paul climbs another staircase which has 13 steps. Does his power change? Explain. b) Another test consists of firing a bullet towards a wooden block from a short distance. Using a gun of mass 3 kg, Paul fires a bullet of mass 0.02 kg with a speed of 300 m/s. i) What is the total momentum before the gun is fired? Explain. ii) Calculate the recoil velocity of the gun after firing. (Ignore the mass of Paul.) iii) The bullet hits and becomes embedded in the wooden block of mass 2.8 kg. Calculate the common velocity with which they continue to move. [3] Physics Form 5 Secondary Track Page 11 of 14

12 iv) Name and state the principle used in part b (ii) and part b (iii). [3] c) During his training Paul wears a helmet that is padded with foam on its inside. Explain in terms of Physics principles why this helps to prevent injury. [2] 11. This question is about methods of heat transfer. Miss Mifsud shows her students the apparatus in Figure 12. It consists of a heat resistant plastic board held vertically by means of two stands. An electric heater is fixed at the centre and three temperature sensors A, B and C are installed at the same distance from the heater. The heater is switched on and the temperature of each sensor is measured at two minute intervals for ten minutes. board A Temperature 50 B ( C) heater C stands 0 Figure 12 a) The results are plotted as shown. Label correctly each graph obtained for sensors A, B and C. b) The room temperature = C [1] c) Name the method of heat transfer through which heat reaches all the sensors. [1] d) The heat cannot be transferred to the sensors by conduction. Why? [2] e) Explain the results she obtains time /(minutes) [3] Page 12 of 14 Physics Form 5 Secondary Track [3]

13 f) On Figure 12, mark with a D, a sensor which when placed at the same distance from the heater registers the same temperature change as A. [2] g) Before starting the experiment, Miss Mifsud noticed that one of the sensors was shiny, while the other two were black. She replaced the shiny one with a black one. Explain why she did so. [3] h) Name TWO ways through which the results can be obtained in a shorter time. [2] i) How would the results of this experiment change if it is carried out in a vacuum? Explain. [3] 12. This question is about electricity. a) Complete the following table. Component Symbol Function Diode LDR Its resistance varies according to light intensity. b) A student is provided with a metal wire, a d.c. supply, a switch, connecting wire, an instrument to measure current and one to measure voltage. i) In the space provided draw the circuit required to find its resistance at room temperature. Label all components. [3] ii) Explain briefly how the result is obtained. [5] [3] Physics Form 5 Secondary Track Page 13 of 14

14 c) A sandwich toaster has a power rating of 800 W and is used daily for 20 minutes. i) Given that 1 kwh costs 18 c, calculate the total cost of using the toaster for 2 weeks. ii) Calculate the current flowing through the toaster if its voltage is 230 V. iii) Suggest a suitable fuse rating for the toaster. d) A current of 0.8 A flows through the 3 Ω resistor in Figure 13. i) Calculate the potential difference across the 3 Ω resistor. 6 V R 3 [1] ii) Calculate the current flowing through the 2 Ω resistor. 2 Y Figure 13 iii) Calculate the resistance of resistor R. Page 14 of 14 Physics Form 5 Secondary Track

YEAR 11 PHYSICS TIME: 2 hours

DIRECTORATE FOR QUALITY AND STANDARDS IN EDUCATION Department of Curriculum Management Educational Assessment Unit Annual Examinations for Secondary Schools 2017 Track 2 YEAR 11 PHYSICS TIME: 2 hours Name: