THE UNITED REPUBLIC OF TANZANIA NATIONAL EXAMINATIONS COUNCIL

CERTIFICATE OF SECONDARY EDUCATION EXAMINATION 

031/1          PHYSICS 1

(For Both School and Private Candidates) 

Time: 3 Hours                   Friday, 09^th November 2018 a.m. 

Instructions 

1. This paper consists of sections A, B and C with a total of eleven (11)  questions.
2. Answer all questions in sections A and B and one (1) question from section C.
3. Calculators, cellular phones and any unauthorized materials are not allowed in the examination room.
4. Write your Examination Number on every page of your answer booklet(s).
5. Where necessary the following constants may be used:

(i)Acceleration due to gravity, g = 10 m/s² or 10 N/kg

(ii)Specific heat capacity of mercury is 1395 J/kg°C

(iii) 1g of water is equivalent to 1 cm³ 

(iv)    Pi = 3.14.            

SECTION A (30 Marks)

Answer all questions in this section.

1. For each of the items (i) - (x), choose the correct answer among the given alternatives and write its letter besides the item number in the answer booklet provided.

(i)The correct formula to find the elastic force constant (k) of a spring is

1. Tension/extension
2. mass/extension
3. extension/mass
4. extension/tension
5. tension/mass

(ii) Why is oil used as a lubricant?

1. It has low density.
2. It is highly viscous.
3. It is flammable.
4. it is inflammable    
5. It is less viscous.

(iii)Which one is a characteristic of a plane mirror?

1. It forms image which is real and opaque.
2. It forms an image which is larger than the object.
3. It forms an image which is real and laterally inverted
4. It forms an image which has the same size as the object.
5. It forms an image which is smaller in size than the object.

(iv) Which one is not a region of electromagnetic spectrum?

1. radio waves
2. . x-rays
3. infrared light
4. ultraviolet light 
5. invisible light waves.

(v)  What quantity of heat is required to raise the temperature of 25 kg sample of mercury from 20°C to 30°C?

1. 1,743,750J
2. 348,750J
3. 345,750J
4. 413,750J
5. 1,550,750J

(vi)When silicon element is doped with phosphorus atoms, it produces

1.   a p-type semiconductor
2. force
3. an intrinsic semiconductor
4. a bipolar semiconductor
5. an n-type semiconductor

(vii) Which of the following is an example of a scalar quantity?

1. Electric current 
2. Force
3. Velocity
4. Displacement
5. Acceleration

(viii)What role does the iris play in the human eye?

1. To hold the lens in position.
2. To prevent internal reflection.
3. To control the size of the pupil.
4. To control the thickness of the lens.
5. To protect the eye from light.

(ix) Asteroids which manage to reach the earth surface are called

1. stars.
2. meteors
3. meteorites.
4. constellations.
5. comets.

(x) What will be the resistivity of a wire 2 metres long with a cross-sectional area of 0.50 mm² and a resistance of 2.20? 

1.  5.5 x 10^-7 ?m 
2.  6.5 xlO^-7?m 
3. 2.3 x 10^-7 ?m 
4.  1.1 x 10-⁶?m
5.  5.5 x 10^-6?m.