Waves begin to "feel bottom" when the depth of water is equal to one-half the wavelength equal to the wavelength twice as great as the wavelength three times as great as the wavelength

Waves begin to "feel bottom" when the depth of water is equal to one-half the wavelength. As the wave approach a shallow shore, its path is altered. This distortion caused the waves to become slow. As the wave becomes higher, the length of the wave decreases.

Idk bro sorry  lava is hotter then magma but im  not sure about it alll