Which pairs of instruments is used for measuring lengths?
A.A ruler and a measuring cylinder
B.A micrometer screw gauge and a beam balance
C.A vernier caliper and a micrometer screw gauge
D.A pipette and a vernier caliper
E.A beam balance and a spring balance
2.5 marks
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.
List A
List B
It produces fast moving electrons when heated at high temperature.
A Perrin tube
Traces the direction of cathode rays in a cathode ray tube.
B X-plate
Deflects the electron beam vertically.
C Anode
Deflects the electron beam horizontally.
D Cathode
Accelerates the ejected electrons to the screen
E Y-plate
F Maltese cross tube
G Vacuum
(i)
It produces fast moving electrons when heated at high temperature.
1 mk
(ii)
Traces the direction of cathode rays in a cathode ray tube.
1 mk
(iii)
Deflects the electron beam vertically.
1 mk
(iv)
Deflects the electron beam horizontally.
1 mk
(v)
Accelerates the ejected electrons to the screen
1 mk
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Section B
3.10 marks
Three plane mirrors are arranged along three sides of a square. A ray of light is incident on the left side mirror at its midpoint with an angle of incidence of 40° so that the ray is afterwards reflected by other mirrors.
(a)
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
(b)
Explain two functions of the shutter in a camera.
4 mk
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4.6 marks
Use a well labelled diagram to explain the working principle of a hydraulic braking system.
(a)
Use a well labelled diagram to explain the working principle of a hydraulic braking system.
6 mk
(b)
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?
4 mk
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5.5 marks
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.
(a)
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
(b)
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%.
5 mk
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6.5 marks
Carefully study Figure 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.
(a)
Carefully study Figure 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
(b)
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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7.10 marks
In Figure 2, the labels A, B, C and D are identical electric bulbs connected in a circuit.
(a)
Explain what will happen to the bulbs A, B and D when bulb C blows off and the key K is closed.
4 mk
(b)
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?
6 mk
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8.10 marks
Figure 3 shows the profile of a radio wave. Study it carefully and determine its wavelength.
(a)
Figure 3 shows the profile of a radio wave. Study it carefully and determine its wavelength.
4 mk
(b)
Explain how an earthquake occurs.
6 mk
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Section C
9.6 marks
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?
(a)
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
(b)
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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10.2 marks
From part (b), determine the effective resistance.
(a)
Distinguish the concepts of conductors, semiconductors and insulators in terms of their energy bands.
6 mk
(b)
Figure 4 shows an electric circuit. Carefully study it and calculate the value of current x and r.
4 mk
(c)
From part (b), determine the effective resistance.
2 mk
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11.4 marks
Form One students were shouting in their classroom. Briefly explain how other students in the next room can hear them shouting.
(a)
Describe the mechanism of doping intrinsic semiconductor to obtain p-type semiconductor.
6 mk
(b)
Why most of the transistors in use are n-p-n transistors?
2 mk
(c)
Form One students were shouting in their classroom. Briefly explain how other students in the next room can hear them shouting.
4 mk
