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Question
State the condition when a lens is called an equi-convex or equi-concave.
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Solution
A lens is called an equiconvex or equiconcave when radii of curvature of the two surfaces of lens are equal.
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RELATED QUESTIONS
The diagram below shows a lens as a combination of a glass slab and two prisms.
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The diagram given below shows the position of an object OA in relation to a converging lens whose foci are at F1 and F2.

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