A study that deals with constellation, solar system and cosmos is referred to as

With the aid of a diagram, compare the penetrating ability of the three types of radiations on a piece of paper, aluminum sheet and lead block.

1. With the aid of a diagram, compare the penetrating ability of the three types of radiations on a piece of paper, aluminum sheet and lead block. (5 mk)
2. Compare the effect of frequency and amplitude to musical sound. Give two points each. (4 mk)

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Describe the three uses of constellations.

1. Why are the surface waves more dangerous than the primary and secondary waves? (3 mk)
2. Describe the three uses of constellations. (6 mk)

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Match the items in List A with the appropriate descriptions in List B. Write the letter of the correct item on the space provided beside each item in List A. (6 marks) List A (i) Wheelbarrow (ii) Wheel and axle (iii) Hydraulic press (iv) Tong (v) Claw hammer (vi) Inclined plane List B A: Is useful in drawing water from a borehole. B: Applies the principle of first class lever. C: Its velocity ratio increases by increasing the length of the ramp. D: The effort is between the load and fulcrum. E: Operates based on the principle of transmission of pressure in fluids. F: Carries objects from one point to another horizontally.

1. Wheelbarrow (1 mk)
2. Wheel and axle (1 mk)
3. Hydraulic press (1 mk)
4. Tong (1 mk)
5. Claw hammer (1 mk)
6. Inclined plane (1 mk)

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3 (a) A convex mirror is often used as the wing mirror of a car instead of plane mirror. Justify this statement giving one point. (3 marks) (b) A camera is used to take a close-up picture of an object 3 cm tall. If the object is positioned 24 cm in front of the lens and a focused image is formed on the film 12 cm behind the lens, determine the focal length of the camera lens and the height of the image formed on the film. (6 marks)

1. A convex mirror is often used as the wing mirror of a car instead of plane mirror. Justify this statement giving one point. (3 mk)
2. A camera is used to take a close-up picture of an object 3 cm tall. If the object is positioned 24 cm in front of the lens and a focused image is formed on the film 12 cm behind the lens, determine the focal length of the camera lens and the height of the image formed on the film. (6 mk)

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4. (a) Why is it not be practical to make a barometer with water instead of mercury! (4 marks) (b) A force of 200 N and 20 cm long spanner and 150 N and 30 cm long spanner were separately used to loosen the left and right front car tire nuts, respectively. Show that the 30 cm long spanner will be more effective than the 20 cm long spanner. (5 marks)

1. Why is it not be practical to make a barometer with water instead of mercury! (4 mk)
2. A force of 200 N and 20 cm long spanner and 150 N and 30 cm long spanner were separately used to loosen the left and right front car tire nuts, respectively. Show that the 30 cm long spanner will be more effective than the 20 cm long spanner. (5 mk)

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5 (a) Why while swimming, the swimmer pushes the water backward with his hands? (4 marks) (b) Figure 1 shows two simple machines A and B having the same efficiency. Justify that simple machine A requires minimum effort to raise a load of 5000 N. (5 marks) Figure 1 shows two simple machines A and B having the same efficiency. Justify that simple machine A requires minimum effort to raise a load of 5000 N. Radius R=50 cm Radius r= 10 cm Effort L= 5000N Effort L= 5000 N Simple Machine A Simple Machine B Figure 1

1. Why while swimming, the swimmer pushes the water backward with his hands? (4 mk)
2. Figure 1 shows two simple machines A and B having the same efficiency. Justify that simple machine A requires minimum effort to raise a load of 5000 N. (5 mk)

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6 (a) Figure 2 shows a bimetallic thermostat strip used to regulate the temperature of the room by using a heater and a cooler. Which device between A and B is a heater? Justify your answer. (4 marks) Aluminium A B Steel Figure 2

1. Figure 2 shows a bimetallic thermostat strip used to regulate the temperature of the room by using a heater and a cooler. Which device between A and B is a heater? Justify your answer. (4 mk)

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Why a low voltage supply should have a low internal resistance. Explain by using an appropriate formula.

1. By drawing circuit diagrams supported by the graphs, compare the charging and discharging processes of a capacitor given that you are provided with a cell (E), a voltmeter (V), a switch (S), a capacitor (C), a resistor (R) and connecting wires. (6 mk)
2. Two wires A and B of the same material and length have the cross-sectional area in the ratio 2:1. If the same potential difference is applied across each wire, comment on the amount of current flowing between the wires A and B. (6 mk)
3. Why a low voltage supply should have a low internal resistance. Explain by using an appropriate formula. (3 mk)

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Transistor is a three terminal device that is used to amplify the strength of weak signals. Draw the NPN transistor cTCuit connections with four terminals in the following modes: Common Base (C5), Common Emitter (CE) and Common Collector (CC) indicating the input and output circuits.

1. Transistor is a three terminal device that is used to amplify the strength of weak signals. Draw the NPN transistor cTCuit connections with four terminals in the following modes: Common Base (C5), Common Emitter (CE) and Common Collector (CC) indicating the input and output circuits. (6 mk)
2. How will the penetrating power of X rays be affected when their wavelength is reduced? (2 mk)
3. When a speaker is brought near to a Television (TV) operating using cathode ray tube, the picture on the screen is affected but when taken away, the picture becomes normal. Account for this observation. (5 mk)
4. How will the penetrating power of X rays be affected when voltage across X-ray tube is increased? (2 mk)

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