What happens to waves during reflection?

During reflection, waves encounter a boundary, such as the surface of water or a solid object, and reverse their direction upon hitting that boundary. This process involves the wave bouncing back into the medium it came from. The key point is that the energy contained in the wave is not lost but redirected; thus, the wave travels away from the surface after hitting it.

This behavior can be observed in various types of waves, including sound waves reflecting off walls or light waves bouncing off mirrors. The angle at which the wave approaches the boundary is equal to the angle at which it reflects away, a principle known as the law of reflection.

The other possibilities presented do not accurately describe the phenomenon of reflection. For instance, while a wave could theoretically continue traveling in the same direction if it were not to encounter a boundary, this does not represent reflection. Likewise, dissipating energy into the medium refers more to absorption or scattering rather than reflection, and changing frequency is associated with phenomena like the Doppler effect rather than reflection itself. Therefore, reversing direction after hitting a surface is the defining characteristic of reflection.