What happens when light strikes the surface of water at different angles?

When light strikes the surface of water at different angles, several things can happen depending on the angle of incidence:

1. At small angles (close to perpendicular):
   Most of the light passes into the water but bends toward the normal because water is denser than air. This bending is called refraction.
2. At moderate angles:
   Part of the light still refracts into the water, bending toward the normal, while some light reflects off the surface. So, you get a combination of reflected and refracted rays.
3. At the critical angle:
   The refracted light travels along the surface boundary between air and water. This is the special angle where the refracted ray bends exactly at the interface.
4. At angles greater than the critical angle:
   No light passes into the air; instead, total internal reflection occurs. All the light reflects back into the water.

So, depending on the angle, light can be mostly refracted into the water, partially reflected, or fully reflected inside the water. This behavior explains many natural phenomena like the sparkle of water surfaces, underwater visibility, and mirages.