Question

What do all mechanical waves have in common A they are all able to move through empty space B They all vibrate in the same direction as the wave motion C they must move through a medium D They all vibrate at right angle to the direction the wave is moving

Answer 1

All mechanical waves have in common **C: they must move through a medium**. Mechanical waves require a medium (solid, liquid, or gas) to propagate, unlike electromagnetic waves, which can travel through a vacuum.