What is one difference between an electromagnetic wave and a mechanical wave?
A.
A mechanical wave can travel through a vacuum. An electromagnetic wave must have a medium to travel through.
B.
An electromagnetic wave can travel through a vacuum. A mechanical wave must have a medium to travel through.
C.
An electromagnetic wave moves parallel to the direction of the wave's travel. A mechanical wave can move only perpendicular to the direction of the wave's travel.
D.
An electromagnetic wave moves perpendicular to the direction of the wave's travel. A mechanical wave can move only parallel to the direction of the wave's travel.