The radius of curvature of a spherical mirror is 20 cm. What is its focal length?

Explanation

Radius of curvature, R = 20 cm
Radius of curvature of a spherical mirror,
`R = 2 xx" focal length (f)"`
R = 2f
20 = 2f
`implies f=(20)/(2)= 10 cm`
Therefore, the focal length of given spherical mirror is 10 cm.