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 November 05, 2004 a.m.

Instructions

1. This paper consists of sections A, B and C.

2. Answer all questions in section A and B, and two (2) questions from section C.

3. Cellular phones are not allowed in the examination room.

4. Electronic calculators are not allowed in the examination room.

5. Write your Examination Number on every page of your answer booklet(s). 6. Whenever necessary use the following constants:

Specific heat capacity of Aluminium,

CAL = 920 J kg^­1 K^­1

Specific latent heat of fusion of Aluminium LAL = 3.2×105 J kg­1

Melting point of Aluminium = 660°C

SECTION A (20 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.

(i) The movement of liquid from low to high concentration through a semi­permeable membrane is called

1. diffusion
2. fusion
3. osmosis 
4. osmotic pressure
5. Brownian motion.

(ii) What would happen to the planets moving around the sun if the gravitational force suddenly disappeared?

1. The planets would fuse together
2. The planets would fly far away opposite to the sun’s direction
3. The planets would move tangentially to their orbits in a straight line
4. Some planets would fall onto other planets nearby
5. Some of the planets would collide.

(iii) In a correctly fused plug, the cartridge fuse is connected between the

1. neutral lead and live lead
2. live lead and live pin
3. neutral lead and earth lead
4. live lead and earth pin
5. positive lead and negative lead.

(iv) The weight of a body is 20 N in air, 15 N when totally immersed in water and 18 N when totally immersed in liquid L. What is the relative density of L?

1. 5 N
2. 0.4 
3. 0.4 N 
4. 2.5 
5. 0.5.

(v) A certain wave has a period of 0.2 sec and a wavelength of 60 cm. What is the velocity of the wave in cm/s?

1. 30 
2. 0.30 
3. 12 
4. 3 
5. 300.0.

(vi) A convex mirror always forms

1. real images only
2. virtual images only
3. inverted real images only
4. magnified virtual images only
5. real and virtual images depending on the position of the object.

(vii) One advantage of a lead­acid accumulator is that

1. its internal resistance is high
2. no chemicals are used
3. its e.m.f. is more than 15 V
4. it can be recharged
5. it supplies only a small current.

(viii) The unit of electric charge is

1. ampere 
2. volta
3. coulomb 
4. ohm 
5. ameter.

(ix) A wire carries a current i horizontally between the magnetic poles N and S which face each other on a table (see Fig. 1 below).

Fig. 1

The direction of the force on the wire due to the magnet is

1. from N to S
2. from S to N
3. opposite to the current direction
4. vertically upwards 
5. in the direction of the current.

(x) Which of the following statements is not correct?

1. The forbidden energy gap in conductors is very wide
2. The majority charge carriers in p­type semi­conductors are holes
3. An integrated circuit (IC) has a combination of several resistors and transistors built out of the same crystal.
4. Cathode rays consist of a beam of accelerated electrons
5. X­rays are electromagnetic radiation of short wavelength.