Fusion is not usually used for generating electric power because

• A. no energy is released when fusion takes place
• B. very high temperatures are required to initiate fusion reaction
• C. the raw materials needed is not easily available
• D. heavy nuclei are involved

Explain why it is desirable to install an air conditioner near the ceiling of a room and not close to the floor.

If no net force acts on an object, the object maintains a state of rest or constant speed in a straight line. The above is a statement of Newton's

• A. first law of motion
• B. second law of motion
• C. third law of motion
• D. law of universal gravitation

A uniform metre rule is balanced on a fulcrum placed at the 35cm mark by suspending a mass of 120g at the 10cm mark. Calculate the mass of the metre rule.

• A. 60g
• B. 80g
• C. 120g
• D. 200g

Which of the following will reduce the frequency of oscillation of a simple pendulum?

• A. Increasing the mass of the bob
• B. Decreasing the mass of the bob
• C. Increasing the length of the string
• D. Decreasing the length of the string

The electrical properties of germanium can be altered drastically by the addition of impurity. This process is referred to as

• A) saturation
• B) bonding
• C) amplification
• D) dopping

Which of the following instruments is best for measuring the diameter of a thin constantan wire?

• A. callipers
• B. metre rule
• C. micometer screw guage
• D. vernier callipers

(a) State Heisenberg's uncertainty principle.

(b) Mention two phenomena that can only be explained in terms of the particulate nature of light.

A travelling wave of amplitude 0.80 m has a frequency of 16 Hz and a wave speed of 20 ms^-1

Calculate the wave number of the wave.

• A. 3
• B. 4
• C. 5
• D. 2

A radioisotope has a decay constant of 10^−7s^−1. The average life of the radioisotope is

• A. 1.00 x 10⁷s
• B. 6.93 x 10⁶s
• C. 1.00 x 10^-7s
• D. 6.93 x 10⁷s