THE UNITED REPUBLIC OF TANZANIA NATIONAL EXAMINATIONS COUNCIL OF TANZANIA CERTIFICATE OF SECONDARY EDUCATION EXAMINATION
031/1 PHYSICS 1
(For Both School and Private Candidates)
Time: 3 Hours Friday, 08th November 2019 a.m.
Instructions
SECTION A (15 Marks)
Answer all questions in this section.
1. For each of the items (i) - (x), choose the correct answer from among the given alternatives and write its letter beside the item number in the answer booklet provided.
(i) Which pairs of instruments would you use to correctly measure the diameter of a small ball bearing?
(ii) A piece of a cork of volume 100 cm 3 is floating on the surface of water. If the density of the cork is 0.25 g cm -3 , what volume of the cork is immersed in the water?
(iii) A layer of colorless water floating on a blue copper (Il) sulphate solution becomes blue after sometime. Which physical process supports the observation made?
(iv) A pin-hole camera 200 mm long produces an image of 2 mm diameter of the sun. If the sun's distance from the earth is about km , what is the diameter of the sun?
(v) Which phenomena is a result of the earth being exactly along the same line between the centre of the sun and the moon?
(vi) Which metals become strongly magnetized when subjected to a magnetic field?
(vii) A body moved upward a distance of 20 m. Calculate the time taken to reach the maximum height.
(viii) The temperature of a certain liquid is measured to be 300 K. What will be its temperature in degree centigrade?
(ix)Which factors influence friction between tyres of a car moving with constant speed and the surface of the road?
(x) When the sun shines on the dark-coloured driving wheel of a car, the wheel feels warm. Why?
2. Match the properties of radiations in List A with the corresponding radiations in List B by writing the letter of the correct response beside the item number in the answer booklet provided.
The responses can be used more than once.
LIST A | LIST B |
| ![]() |
SECTION B (60 Marks)
Answer all questions in this section.
3. (a) In a light experiment, a narrow beam of light directed onto a glass prism leaves the prism and falls on a white screen. Draw a labelled diagram to show the experimental set-up and observation seen on a screen. (5 marks)
View Ans(b) Explain two ways in which lens cameras differ from human eye. (5 marks)
View Ans4. (a) Why a bubble of air increases in volume as it rises from the bottom of a pond of water to the surface? Briefly explain. (5 marks)
View Ans(b) A half meter rule AB is freely pivoted at 18 cm from end A and balances horizontally when a body of mass 35 g is hung 48 cm from end B. Calculate the mass of the rule. (5 marks)
View Ans5. (a)Figure 1 shows a simple machine B which has to be used to pull the packing case of 2000N into the car by an effort of 500 N. Calculate the efficiency of machine B. ( 5 marks)
Figure 1
View Ans(b) With the aid of a clearly labeled diagram, describe an experiment to investigate the relationship between the force acting on a body and the acceleration produced. ( 5 marks)
View Ans6. (a) A beaker containing ice is heated from -5°C to 0°C and then from 0°C to 15°C. With the aid of a diagram, explain the variation of density with temperature. ( 5 marks)
View Ans(b) A brick at 20°C has a dimension of 30 cm, 18 cm and 10 cm for length, width and height respectively. If a brick is heated to a new temperature of 150°C, calculate the new dimensions. ( 5 marks)
View Ans7(a) With the aid of a diagram, explain the function of a fuse in an electrical appliance. ( 5 marks)
View Ans(b) A circuit in a house is protected by a 10 A fuse. The circuit is connected to the 240 V mains.
The following appliances are connected to the circuit:
Appliance | Power rating |
Bulb 1 | 100 W |
Bulb 2 | 75 W |
TV | 300 W |
Heater | 1500 W |
Determine whether the fuse will blow on or off if all appliances are turned on. ( 5 marks)
View Ans8(a) (a) Why the inner core of the earth is solid while the outer core is liquid? Briefly explain. ( 5 marks) Soln.
View Ans(b) The frequency obtained from a plucked string when the tension is 2 N is 400 Hz. Calculate the frequency when the tension is increased by 6 N. ( 5 marks)
View AnsSECTION C (25 Marks)
Answer two ( 2) question from this section.
9. (a) Carefully study Figure 2 which shows a design for an electrical operation model for lifting metal objects. Briefly explain three things you can do so that a heavier iron metal block can be lifted. ( 6 marks)
Figure 2
View Ans(b) Why a musician must retune a stringed instrument if its temperature changes? (2.5 marks)
View Ans(c) During a thunderstorm, the time between the flash of light and the thunder is 10 s. How far away is the thunderstorm? (4 marks)
View Ans10. (a) A sample of carbon isotope 146C has a half-life of 5700 years. What fraction of 146C will remain after 11400 years? ( 6 marks)
View Ans(b) Describe the construction and mode of action of the PN junction semiconductor. ( 6.5 marks)
View Ans11. (a) Electrical energy is distributed in all parts of Tanzania by the National grid system which transmits alternating current at a very high voltage. Explain why is it necessary to have a very high voltage? ( 5.5 marks)
View Ans(b) A generator producing a varying current from 0 to 10 A was allowed to flow in a coil of magnetic field. After a time interval the current was observed to be 4 A. Describe how back e.m.f. Was induced in a self-induction (7 marks)
View Ans