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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

`sqrt(f_1/f_2)`

B

`sqrt(f_2/f_1)`

C

`(f_1+f_2)/(2)`

D

`(f_1+f_2)/(f_1f_2)`

Text Solution

Verified by Experts

The correct Answer is:
A, B, D
Focal length of combination `1/f=(1)/(f_1)+(1)/(f_2)`
`therefore`Power of combination P =`1/f=(f_1+f_2)/(f_1f_2)`
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