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Subject: Science , asked on 16/2/10

If far point or near point of a person's eye is given how to calculate Power of lens required for the person?

If far point is given take that as the image distance[v]...and object distance[u] as infinity...& if near pt is giiven take 'u' as 25cm, thn use the lens formula to find the focal length....also remember 1infinity=0.....after getting the focal length substitute tht value in the formula 1f to get the power of the lens...

~thnx~

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see Nitin....far point of a normal person is infinity rite?yeah we've learnt tht...so we take tht as 'u' when far point of a myopic eye is given.....& always choose the given value as the image distance coz tht is the image formed on retina of a myopic/hypermetropic eye....& 'u' will be 25cm/infinity depending on the question.......

thnks a lot for the thumb up!

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