WAEC Past Questions and Answers - Page 3456

17,276.

Which of the following factors can affect the speed of sound in air?

i. The temperature of the surrounding
ii. The direction of the wind
iii. The pitch of the sound.

A.

i and ii only

B.

ii and iii only

C.

i and iii only

D.

i, ii and iii

Correct answer is A

No explanation has been provided for this answer.

17,278.

When an object is placed at the centre of curvature of a concave mirror, its image is formed at

A.

the focus

B.

infinity

C.

the centre of curvature

D.

a distance twice the radius of curvature

Correct answer is C

No explanation has been provided for this answer.

17,279.

In which of the following piece of apparatus is the radius of curvature equal to twice the focal length?

A.

converging lens

B.

diverging lens

C.

converging mirror

D.

parabolic mirror

Correct answer is C

No explanation has been provided for this answer.