A hypermetropic person whose near point is at `100 cm` wants to read a book at `25 cm`. Find the nature and power of the lens needed.

A hypermetropic person whose near point is at `100 cm` wants to read a

1.	A hypermetropic person whose near point is at `100 cm` wants to read a book at `25 cm`. Find the nature and power of the lens needed.
Answer» Here, `u = - 25 cm, v = - 100 cm`, `f = ?` As `(1)/(f) = (-1)/(u) + (1)/(v)` `:. (1)/(f) = (1)/(25) - (1)/(100) = (4 - 1)/(100) = (3)/(100)` `f = (100)/(3) cm = 33.3 cm` `P = (100)/(f) = (100)/(100//3) = 3` dioptre The lens must be converging.

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A hypermetropic person whose near point is at `100 cm` wants to read a book at `25 cm`. Find the nature and power of the lens needed.

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