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

`(f_1f_2)/(f_1-f_2)`

`sqrt(f_1f_2)`

`(f_1f_2)/(f_1+f_2)`

`(f_1+f_2)/(f_1f_2)`

Text Solution

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The correct Answer is:

A, B, C

`1/f=(1)/(f_1)+(1)/(f_2)`

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