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Radius of curvature of a concave mirror ...

Radius of curvature of a concave mirror is 20 cm, then its focal length is ...... cm.

A

- 20 cm

B

+ 20 cm

C

– 10 cm

D

+ 10 cm

Text Solution

Verified by Experts

The correct Answer is:
A, C
For spherical mirror,
R=2f
`therefore` 20=2f `therefore` f = -10 cm
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