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One concave and one convex lens have sam...

One concave and one convex lens have same focal length. If they are kept in contact, combination behaves as .......

A

Concave lens

B

Convex lens

C

Transparent plane plate

D

Curved surface

Text Solution

Verified by Experts

The correct Answer is:
A, C
`1/f_1=1/f+1/f`
`1/f_1=(1)/(-f)+1/f` [`because` For concave lens f is negative and for convex lens f is positive]
`therefore 1/f_1=0` `thereforef_1=infty`
`therefore` Transparent plane plate.
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