Question

The point on the principal axis to which the parallel beams of light converge after reflection from a concave mirror is called ______________.

Answer 1

1. There are two types of spherical mirrors; a concave mirror and a convex mirror.
2. A concave mirror is called a converging mirror.
3. There is a point on the principal axis of a concave mirror at which all the light rays parallel to the principal axis of the mirror converge after reflection from the mirror.
4. The point is called principal focus or simply focus of the concave mirror.

Thus, the point on the principal axis to which the parallel beams of light converge after reflection from a concave mirror is called principal focus.