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प्रश्न
The radius of curvature of a spherical mirror is 20 cm. What is its focal length?
उत्तर
Radius of curvature, R = 20 cm
Focal length (f) = `R/2`
f = `R/2`
f = `20/2`
f = 10 cm
Hence, the focal length of the given spherical mirror is 10 cm.
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