Which pairs of instruments is used for measuring lengths?

Match the functions of the features of cathode ray tube in List A with the corresponding features in List B by writing the letter of the correct response beside the item number in the answer booklet provided.

1. It produces fast moving electrons when heated at high temperature. (1 mk)
2. Traces the direction of cathode rays in a cathode ray tube. (1 mk)
3. Deflects the electron beam vertically. (1 mk)
4. Deflects the electron beam horizontally. (1 mk)
5. Accelerates the ejected electrons to the screen (1 mk)

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Explain two functions of the shutter in a camera.

1. Draw the appropriate path of the ray and calculate the angle through which the ray is turned at each of the three reflections. (6 mk)
2. Explain two functions of the shutter in a camera. (4 mk)

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A uniform pencil AB weighing 40 g can be balanced horizontally on a knife edge at 2 cm from the end A when a mass 60 g is hung from this end. What is the length of a pencil?

1. What is the length of a pencil? (4 mk)
2. Use a well labelled diagram to explain the working principle of a hydraulic braking system. (6 mk)

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A hydraulic press consists of a pump, load and two cylinders in which the larger cylinder is eight times the diameter of a smaller one. Use a well labelled cross-sectional diagram of a hydraulic press to determine the value of mechanical advantage of this machine if it is working with efficiency of 90%.

1. Why the recoil velocity of a gun is much less than the velocity of the bullet? Explain by using the principle of conservation of linear momentum. (5 mk)
2. Use a well labelled cross-sectional diagram of a hydraulic press to determine the value of mechanical advantage of this machine if it is working with efficiency of 90%. (5 mk)

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How would the dimensions of a newly constructed Tanzania standard gauge rail line change during the summer and winter days?

1. Explain what will happen to the bulbs P and Q in relation to the water levels X and Y when the heater is turned on. (5 mk)
2. How would the dimensions of a newly constructed Tanzania standard gauge rail line change during the summer and winter days? (5 mk)

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Rutherford proton-neutron model shows that there are no electrons in the nucleus of an atom. How is it possible for a radioactive element to emit beta particles (electrons) from its nucleus?

1. Explain what will happen to the bulbs A, B and D when bulb C blows off and the key K is closed. (4 mk)
2. How is it possible for a radioactive element to emit beta particles (electrons) from its nucleus? (6 mk)

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Explain how an earthquake occurs.

1. Study it carefully and determine its wavelength. (4 mk)
2. Explain how an earthquake occurs. (6 mk)

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You are provided with a moving coil galvanometer of a coil resistance 20Ω and can carry a maximum current of 15 mA. How will you design this galvanometer to register 10 mA full scale deflection?

1. Show clearly three ways in which a piano wire can be tuned to emit a note of the same frequency as a vibrating turning fork. (6 mk)
2. You are provided with a moving coil galvanometer of a coil resistance 20Ω and can carry a maximum current of 15 mA. How will you design this galvanometer to register 10 mA full scale deflection? (6 mk)

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From part (b), determine the effective resistance.

1. From part (b), determine the effective resistance. (2 mk)
2. Distinguish the concepts of conductors, semiconductors and insulators in terms of their energy bands. (6 mk)
3. Carefully study the electric circuit shown in Figure 4 and calculate the value of current x and r. (4 mk)

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Form One students were shouting in their classroom. Briefly explain how other students in the next room can hear them shouting.

1. Form One students were shouting in their classroom. Briefly explain how other students in the next room can hear them shouting. (4 mk)
2. Describe the mechanism of doping intrinsic semiconductor to obtain p-type semiconductor. (6 mk)
3. Why most of the transistors in use are n-p-n transistors? (2 mk)

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