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Question
What is the relation between the focal length and radius of curvature of a spherical mirror (concave mirror of convex mirror)? Calculate the focal length of a spherical mirror whose radius of curvature is 25 cm.
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Solution
The relation between the focal length and radius of curvature of a spherical mirror is as follows:
Radius of curvature = 2 x focal length
R = 2f
Given, the radius of curvature 'R' = 25 cm
Then, the focal length `f``=25/2 =12.5cm`
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