Question

6. Define the angle of incidence ?​

Answer 1

Answer:

In geometric optics, the angle of incidence is the angle between a ray incident on a surface and the line perpendicular to the surface at the point of incidence, called the normal. The ray can be formed by any wave: optical, acoustic, microwave, X-ray and so on. 

Answer 2

Answer:

Angle of incident is the angle formed by the incident ray and normal.

Incident ray :: Incident ray is the ray of light that falls on the surface of the mirror