Question

I] Defined Radius of curvature and
pole​

Answer 1

(b) Radius of curvature: Radius of curvature of a spherical mirror is the radius of the hollow sphere of glass of which the mirror is a part. (c) Pole: The centre of a spherical mirror is called its pole.

Answer 2

Radius of curvature:

The distance from the vertex to the center of curvature is known as the radius of curvature (represented by R).

Pole: The centre of reflecting surface. It is represented by letter P.

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