What happens to waves when there is refraction in bays?

A. They spread out.

B. They expend less energy.

C. They erode headlands.

D. They spread out and expend less energy.

Right answer: They spread out and expend less energy.

Physically, refraction is the change of direction and speed that a wave experiences when passing from one medium to another with different refractive index. It only occurs if the wave strikes obliquely on the separation surface of the two media ...

Now, in terms of ocean waves, refraction also implies a change of direction that occurs when the wave experiences a change in its wavelength and speed, having as a consequence the waves to spread out and there is dissipation of the energy of the wave. This change usually occurs due to the depth of the ocean in the wave travel.

Thus, as a wave travels from deep to shallow water, the wavelength is shortened, the speed decreases and the wave is refracted (or curved) into the shallow area to conserve its energy.