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Two similar planoconvex lenses are combi...

Two similar planoconvex lenses are combined together in three different ways as shown in the adjoining figure. The ratio of the focal lengths in three cases will be

A

`2:2:1`

B

`1:1:1`

C

`1:2:2`

D

`2:1:1`

Text Solution

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The correct Answer is:
B
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