Q16 of 52 Page 432

A near-sighted person cannot clearly see beyond 200 cm. Find the power of the lens needed to see objects at large distances.

For a near-sighted person, the point where object is placed, u = ∞


Distance between eye-lens and retina , v = – 200 cm = – 2 m


Using lens formula-



Substituting the values-




Now, the power of the lens becomes –



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