The ability of a lens to converge/diverge a beam of light rays is expressed in terms of its **power** (* P*). It is the inverse of focal length,

*(in meters).*

**f**Hence, power of a lens is given by the relation

The SI unit of power is **dioptre** (**D)**.

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The degree of convergence or divergence of light rays achieved by a lens is expressed in terms of its power. The power of lens {P} is defined as the reciprocal of its focal length. Unit of power of lens is diopter {D}. It is measured in metre.

P=1/f { if in m}.

P=100/f { if in cm}.

P=1/f { if in m}.

P=100/f { if in cm}.

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Hi. Here's a solution of your query...

Power of a lens is the ability of the lens to converge or diverge the rays falling on it.

The power of a lens is denoted as the reciprocal of the focal length of the lens. Power of a lens is denoted by the letter 'P'.

P = 1/f(in metres).

The S.I. unit of power of lens is 'dioptre' (D). The power of a lens is one dioptre if it's focal length (f) is 1 metre.

Regards.

Power of a lens is the ability of the lens to converge or diverge the rays falling on it.

The power of a lens is denoted as the reciprocal of the focal length of the lens. Power of a lens is denoted by the letter 'P'.

P = 1/f(in metres).

The S.I. unit of power of lens is 'dioptre' (D). The power of a lens is one dioptre if it's focal length (f) is 1 metre.

Regards.

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