Revise GCSE Physics

Question:Does anything other than speed and direction change when a wave refracts?

Yes, the wavelength of the wave changes. The wavelength becomes shorter if the waves slows down and becomes longer if the wave speeds up.

Angry face

See diagram. This happens because the frequency of a wave never changes; And speed = frequency x wavelength, so when one of wavelength or speed change the other one must change to in order for the equality to be maintained.