WAEC Physics Past Questions & Answers - Page 38

186.

Which of the following waves requires a material medium for its propagation?

A.

Radio waves

B.

Light waves

C.

Sound waves

D.

X-rays

Correct answer is C

 

- Electromagnetic waves are waves that have no medium to travel whereas mechanical waves need a medium for its transmission

 sound wave is an example of a mechanical wave. Sound waves are incapable of traveling through a vacuum.

187.

The average distance moved by a molecule between collisions is called

A.

molecular distance

B.

intermolecular distance

C.

mean distance

D.

mean free path

Correct answer is D

-  the mean free path is the average distance traveled by a moving particle (such as an atom, a molecule, a photon) between successive impacts .

188.

Which of the following machines does not apply the lever principle?

A.

Claw hammer

B.

Wheelbarrow

C.

Single pulley

D.

sugar tong

Correct answer is C

single pulley is a device composed of a wheel on an axle over which a rope, cord, or similar implement is looped.

189.

How would the capacitance of a parallel plate capacitor be affected if the distance of separation of its plates is decreased? It will

A.

increase in value

B.

decrease slightly

C.

remain unchanged

D.

drop to zero

Correct answer is A

No explanation has been provided for this answer.

190.

An image formed on a screen is always?

A.

inverted

B.

magnified

C.

upright

D.

virtual

Correct answer is A

No explanation has been provided for this answer.