Question

when is the power of the lens...​

Answer 1

Answer:

it is present at its center

Explanation:

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Answer 2

Answer:

The power of a lens is defined as the reciprocal of the focal length. Lens power is measured in dioptres (D). Converging (convex ) lenses have positive focal lengths, so they also have positive power values. Diverging (concave ) lenses have negative focal lengths, so they also have negative power values.

Explanation:

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