Question

# A plano-convex lens fits exactly into a plano-concave lens. Their plane surfaces are parallel to each other. If the lenses are made of different material of refractive indices and and R is the radius of curvature of the curved surface of the lenses, then focal length of the combination is :

A
B
C
D
Hard
Updated on : 2022-09-05
Solution
Verified by Toppr
Correct option is A)

## Lens maker formula:                .......(1)For Plano-convex lens: Using (1),                         For Plano-concave lens:               Using (2),                         Thus focal length of combination,

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