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Two identical equiconvex lenses, each of...

Two identical equiconvex lenses, each of focal length 'f' are placed side by side in contact with each other with a layer of water in between them as shown in the figure. If refractive index of the material of the lenses is greater than that of water, how the combined focal length 'F' is related of 'f'?

A

`Fgtf`

B

`(f)/(2)ltFltf`

C

`Flt(f)/(2)`

D

F=f

Text Solution

Verified by Experts

The correct Answer is:
B
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