Here's why:
* Waves travel through media. Waves are disturbances that propagate through a medium, like sound waves traveling through air or light waves traveling through glass.
* Boundaries affect wave behavior. When a wave encounters a boundary between two different media, it can be reflected, refracted, absorbed, or transmitted. These changes in behavior are what we associate with the separation of the media.
Example:
Imagine a rope tied to a wall. If you shake the rope, the waves travel along the rope and reach the wall (the boundary). At the wall, the waves are reflected back. This reflection is a consequence of the boundary between the rope and the wall, not a wave itself.
Summary:
The separation between two media is not caused by a specific wave, but rather by the physical boundary between them. The waves themselves are affected by this boundary, leading to phenomena like reflection, refraction, absorption, and transmission.
