Which characteristic defines a transverse wave?

A transverse wave is characterized by the movement of particles being perpendicular to the direction of wave propagation. This means that when a transverse wave travels through a medium, the particles of the medium move up and down or side to side, while the wave itself moves forward. A common example of a transverse wave is light or electromagnetic waves, along with waves on a string. Understanding this characteristic is crucial for distinguishing between types of waves, as it contrasts directly with longitudinal waves, where particle motion occurs parallel to the wave direction.