Question

define power of lens​

Answer 1

Answer:

it is defined as the reciprocal of focal length.

P = 1 by f

It's S.I unit is diopter.

Answer 2

power of lens

⟾ Power of lens is defined as the ability of the lens to converge the rays of light falling on it.

⟾ As a convex lens converge the rays of light falling on the power of a convex lens is said to be positive.

⟾ on the other hand, a concave lens diverges the rays falling on it.

⟾ Therefore, the power of a concave lens is said to be negative

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