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Two thin lenses of focal lengths f1 and ...

Two thin lenses of focal lengths f1 and f2, are in contact and coaxial. The power of combination is

A

`(1)/(sqrt(f_(1)f_(2))`

B

`(f_(1)+f_(2))/(2)`

C

`(f_(1)f_(2))/(f_(1)+f_(2))`

D

`(f_(1)+f_(2))/(f_(1)f_(2))`

Text Solution

Verified by Experts

The correct Answer is:
D
`(1)/(f_(eg))= (1)/(f_(1))+ (1)/(f_(2))= (f_(1)+f_(2))/(f_(1)f_(2))= P_(eg)`
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