Which statement describes a characteristic
common to all electromagnetic waves and
mechanical waves?
(1) both types of waves travel at the same speed.
(2) both types of waves require a material medium
for propagation.
(3) both types of waves propagate in a vacuum.
(4) both types of waves transfer energy.

The correct answer is (4).

Explanation:

Electromagnetic wave is the transverse wave. It is produced by the moving charged particle. It travels at the speed of the light. It does not require a medium to travel. It can travel through the vacuum.

In mechanical wave, there is an oscillation of matter. It requires a medium to travel. It cannot travel through vacuum. The three types of mechanical waves are longitudinal wave, transverse wave and surface wave.

The common characteristics to all electromagnetic waves and mechanical waves are both can move through matter and both can occur as a result of a disturbance. This disturbance is a result of wave transfer energy.

Therefore, the common characteristic to all electromagnetic and mechanical waves is both types of waves transfer energy.  

increase masses, decrease separation