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A concave lens has radioi of curvatures ...

A concave lens has radioi of curvatures of 20 cm and 30 cm respectively. If the refrative index of the material of lens is `1.6` it focal length is given by

A

`-30` cm

B

`-25 cm`

C

`-20 cm`

D

`-10 cm`

Text Solution

Verified by Experts

The correct Answer is:
C
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