Which one of the following statements about alpha and beta particles is correct?

Match the times in List A with responses in List B by writing the letter of the correct response beside the item number. List A List B (i) Newton’s 3rd ​Law of motion A Cells with conducting materials used in electrolysis (ii) Kelvin B Used in forming thick and real images (iii) Proton C A measure of electrical work (iv) Voltameters D Can be detected by means of scintillation counter (v) Kwhr E Is used in covering wounds in hospitals (vi) Radiation F The moon is in penumbra of the shadow of the Earth (vii) Intrinsic semiconductor G Action equals reaction (viii) γ-radiation H Thermodynamic temperature (ix) Venus I The moon is in the umbra of the shadow of the Earth (x) Total Lunar eclipse J Rate of change of momentum K Degrees centigrade L Measure of power generated M Heat transfer which requires material medium N Applied in construction for reinforcing concrete structures O A morning star P A positive charge Q The heat transfer that does not require matter R A shooting star S Pure semiconductor in which external impurity is not added T Impure semiconductor with a hole

1. Newton’s 3rd ​Law of motion (1 mk)
2. Kelvin (1 mk)
3. Proton (1 mk)
4. Voltameters (1 mk)
5. Kwhr (1 mk)
6. Radiation (1 mk)
7. Intrinsic semiconductor (1 mk)
8. γ-radiation (1 mk)
9. Venus (1 mk)
10. Total Lunar eclipse (1 mk)

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(a) What is meant by the terms heat capacity and specific heat capacity? State how they are related. (3 marks) (b) Explain briefly how heat losses have been prevented in a vacuum flask. (3 marks) (c) A heater of 500W is used to raise the temperature of 50 kg of material of specific heat capacity of 960J/kg K, from 18°C to 38°C. Assume that all of the heat from the heater is given to the material. Calculate: (i) heat capacity of the material (2 marks) (ii) the time taken in seconds. (2 marks)

1. What is meant by the terms heat capacity and specific heat capacity? State how they are related. (3 mk)
2. Explain briefly how heat losses have been prevented in a vacuum flask. (3 mk)
3. the time taken in seconds. (2 mk)

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(a) (i) Explain the terms opaque and translucent and give an example of each. (2 marks) (ii) Danger signs along the road as well as tail and brake lamps of motor vehicles rear are painted red. Briefly explain the reason behind. (1 mark) (b) What is the basic difference between real and virtual image as formed by curved surfaces. (2 marks) (c) (i) Give two reasons why convex mirror are used as driving mirror? (2 marks) (ii) A convex mirror of focal length 18cm produces an image on its axis 6cm away from the mirror. Calculate the position of the object. (3 marks)

1. Danger signs along the road as well as tail and brake lamps of motor vehicles rear are painted red. Briefly explain the reason behind. (1 mk)
2. What is the basic difference between real and virtual image as formed by curved surfaces. (2 mk)
3. A convex mirror of focal length 18cm produces an image on its axis 6cm away from the mirror. Calculate the position of the object. (3 mk)

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(a) (i) Define the terms astronomy and asteroids. (2 marks) (ii) Is scorpion a galaxy or a constellation? Give reason for your answer. (1 mark) (b) Distinguish between: (i) a planet and a star (1 mark) (ii) a comet and a meteor (1 mark) (c) Which planet in the solar system is (i) closest to the Sun? (1 mark) (ii) furthest from the Sun? (1 mark) (iii) closest to the earth? (1 mark) (iv) surrounded by rings? (1 mark) (v) the second largest planet? (1 mark)

1. Is scorpion a galaxy or a constellation? Give reason for your answer. (1 mk)
2. Distinguish between a comet and a meteor. (1 mk)
3. surrounded by rings? (1 mk)
4. the second largest planet? (1 mk)

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(c) (i) State briefly the variation of the potential over a pear-shaped conductor and the variation of density of the charge. (2 marks) (ii) An electron passes between two plates, one of which A, carries a positive charge and the other B a negative charge. What is the effect on the electron? (2 marks)

1. An electron passes between two plates, one of which A, carries a positive charge and the other B a negative charge. What is the effect on the electron? (2 mk)
2. Explain briefly, with the aid of a circuit diagram, how you would verify Ohm’s law in the laboratory. (3 mk)
3. How would you know when is necessary to recharge an accumulator? (2 mk)

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(a) (i) What is meant by the terms solenoid and electromagnetic induction? (1 mark) (ii) List down two applications of electromagnetics. (1 mark) (b) Describe the structure and mode of action of a simple d.c. motor. (3 marks) (c) (i) Draw a diagram of an electric bell showing the polarity of the electromagnet, the direction of the current, the core, the yoke, spring and the armature. (3 marks) (ii) Explain what will happen to the mode of action of the electric bell if the core and yoke are made of steel instead of soft iron. (2 marks)

1. List down two applications of electromagnetics. (1 mk)
2. Describe the structure and mode of action of a simple d.c. motor. (3 mk)
3. Explain what will happen to the mode of action of the electric bell if the core and yoke are made of steel instead of soft iron. (2 mk)

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(a) (i) What particle are emitted in thermionic emission? Explain why they are emitted. (2 marks) (ii) What do you understand by the term transistor? (1 mark) (b) (i) How a common emitter arrangement of a transistor is stabilized for temperature changes? (2 marks) (ii) Show the circuit symbol for pnp­transistor and npn­transistor. (2 marks) (c) Draw a simple common emitter amplifier circuit using npn­transistor as a current amplifier. (3 marks)

1. What do you understand by the term transistor? (1 mk)
2. Show the circuit symbol for pnp­transistor and npn­transistor. (2 mk)
3. Draw a simple common emitter amplifier circuit using npn­transistor as a current amplifier. (3 mk)

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(a) Define acceleration due to gravity and state Newton’s first Law of motion. (2 marks) (b) An object is seen to fall from an aeroplane and observed to take 15 seconds in reaching the ground. Assuming that air resistance is negligible, calculate: (i) the height of the plane. (2 marks) (ii) the velocity with which the object strikes the ground. (2 marks) (c) (i) Find the average force required to stop a train weighing 200 tons traveling at 54 km/h in two minutes from the application of the brakes. (ii) What distance will the train travel in that time? (4 marks)

1. Define acceleration due to gravity and state Newton’s first Law of motion. (2 mk)
2. the velocity with which the object strikes the ground. (2 mk)
3. What distance will the train travel in that time? (4 mk)

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(a) (i) Distinguish between longitudinal and transverse waves. (1 mark) (ii) Explain how beats are formed. (2 marks) (b) A light wave is refracted into an optically less dense medium. What change will occur in: (i) the frequency (1 mark) (ii) the speed (1 mark) (iii) the wavelength. (1 mark) (c) (i) What is an echo? (1 mark) (ii) A sound is sent out from the ship and its reflection from the floor of the ocean returns one second later. Assuming that the velocity of sound in water is 1500 m/s, how deep is the ocean? (3 marks)

1. Explain how beats are formed. (2 mk)
2. the wavelength. (1 mk)
3. A sound is sent out from the ship and its reflection from the floor of the ocean returns one second later. Assuming that the velocity of sound in water is 1500 m/s, how deep is the ocean? (3 mk)

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(a) (i) Define electromagnetic field. (1 mark) (ii) Show electromagnetic field lines pattern due to a solenoid. (1 mark) (b) With the aid of a well labeled diagram, explain how an electric bell operates. (4 marks) (c) How can you make a galvanometer read (i) higher current values? (2 marks) (ii) higher voltage values? (2 marks)

1. Show electromagnetic field lines pattern due to a solenoid. (1 mk)
2. With the aid of a well labeled diagram, explain how an electric bell operates. (4 mk)
3. How can you make a galvanometer read higher voltage values? (2 mk)

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