(1) The angle made by the incident ray of light with the normal to the surface at the point of incidence is called the angle of incidence.
(2) The angle made by the refracted ray of light with the normal to the surface at the point of incidence is called the angle of refraction.
[Note: The angle e in Fig. is also called the angle of emergence as it is the angle made by the emergent ray with the normal to the surface at the point of emergence.]
