Physics-
General
Easy
Question
Two similar plano-convex lenses are combined together in three different ways as shown in the adjoining figure. The ratio of the focal lengths in three cases will be
- 2 : 2 : 1
- 1 : 1 : 1
- 1 : 2 : 2
- 2 : 1 : 1
The correct answer is: 1 : 1 : 1
In each case two plane-convex lens are placed close to each other, and 
.
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