WAEC Physics Past Questions & Answers - Page 168

836.

During a thunderstorm, lightning and thunder occurred simultaneously in the atmosphere. An observer on the earth surface's sees the lightning flash shortly before hearing the thunder. This is because the

A.

atmospheric pressure is higher at the surface than at the higher altitudes

B.

speed of sound is less than that of light

C.

temperature of the atmosphere decreases with altitude

D.

atmospheric density decreases with altitude

Correct answer is B

No explanation has been provided for this answer.

838.

The image of an optical pin placed at the principal focus of a concave mirror will be formed

A.

between the principal focus and the pole

B.

at the centre of the curvature

C.

between the principal focus and the centre of curvature

D.

at infinity

Correct answer is D

No explanation has been provided for this answer.

839.

A wave travelling from water to glass suffers a change in its speed at the common boundary. Which of the following properties explains this observation?

A.

dispersion

B.

refraction

C.

interference

D.

diffraction

Correct answer is B

No explanation has been provided for this answer.

840.

The basic difference between a transverse wave and a longitudinal wave travelling in the same direction in a medium is in the

A.

amplitude of the wave

B.

wavelength of the wave

C.

direction of vibration of the particles of the medium

D.

period of vibration of the particle of the medium

Correct answer is C

No explanation has been provided for this answer.