Question

What is a spherical mirror, whose inner hollow surface is the reflecting surface, called?

Answer 1

1. A mirror whose polished, reflecting surface is a part of a hollow sphere of glass is called a spherical mirror.
2. Thus, one side of the spherical mirror is made opaque, and the other side acts as a reflecting surface
3. Depending upon the nature of the reflecting surface of a mirror, the spherical mirror may be classified as:
   3.1. Concave mirror: A spherical mirror whose inner hollow surface is the reflecting surface is called a concave mirror.

3.2. Convex mirror: A spherical mirror whose outer bulging surface is the reflecting surface is called a convex mirror.

Hence, a concave mirror is a spherical mirror, whose inner hollow surface is the reflecting surface.