With the help of a ray diagram,show that the angle of incidence is equal to the angle of reflection when a ray is incident on a concave mirror.

(N/A) In the provided ray diagram,$AB$ is the incident ray parallel to the principal axis.
$B$ is the point of incidence on the concave mirror.
$CB$ is the normal to the surface at point $B$,as the line joining the center of curvature $C$ to any point on the mirror is normal to the surface at that point.
According to the laws of reflection,the angle of incidence $(i)$ is equal to the angle of reflection $(r)$.
Thus,$\angle i = \angle r$,where $\angle i$ is the angle between the incident ray $AB$ and the normal $CB$,and $\angle r$ is the angle between the reflected ray $BD$ and the normal $CB$.