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A person has farsightedness with the mi...

A person has farsightedness with the minimum distance he could see early is 75 cm. Calculate the poer of the spectacts necessary to recify the defect.

Text Solution

Verified by Experts

The minimum distance the person could see elarly is, y = 75 cm
The lens should have a focal length of, `f = (y+25cm)/(y-25cm)`
`f=(75cmxx25cm)/(75cm-25cm)=37.5cm`
it is a convex or converging lens.
The power of the lens is, `P = (1)/(0.375m) = 2.67 diopter`
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