The angle between the refracted ray and the normal is called the angle of refraction, often denoted by the symbol r.

Here's a breakdown:

* Normal: An imaginary line drawn perpendicular to the surface at the point where the light ray strikes.

* Incident Ray: The light ray that strikes the surface.

* Refracted Ray: The light ray that bends as it passes from one medium to another.

The angle of refraction is a key concept in understanding how light behaves when it passes from one medium to another (e.g., from air to water). It's related to the angle of incidence (the angle between the incident ray and the normal) and the refractive indices of the two mediums through Snell's Law.