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What is power of a lens?...

What is power of a lens?

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( i) 11,e capacity of a lens to converge or diverge incident rays is called its power (P).
(ii) The power of a lens depends on its focal length (f):
(iii) Power of lens is the reciprocal of focal length in meters.
`therefore "Power of lens" = 1/("focal length (metre)")`
`P = 1/(f(m))`
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