The frequency of a wave does not change as it passes from one medium to another.What will most likely happen if a light wave moves from the air into a solid?

When light enters a solid from air, it usually travels more slowly because solids have a higher refractive index. Its frequency stays constant, and since wavelength equals speed divided by frequency, its wavelength decreases too. Therefore, the speed of the light wave will decrease.

AI-written and checked against the verified answer.