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What is the focal length of a convex len...

What is the focal length of a convex lens of focal length `30 cm` in contact with a concave lens of focal length `20 cm`. Is the system a converging or a diverging lens ? Ignore thickness of the lenses.

A

30 cm

B

`10` cm

C

`-20 cm`

D

`-60 cm`

Text Solution

Verified by Experts

The correct Answer is:
D
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