The near point of a hypermetropic person is `50 cm` from the eye. What is the power of the lens required to enable him to read clearly a book held at `25 cm` from the eye ?

Explanation

Here, `u = -25 cm, v = -50 cm, f = ?`
`(1)/(f)=(1)/(v)-(1)/(u)=(1)/(-50)+(1)/(25)=(1)/(50)`
`f = 50 cm, P = (100)/(50) + 2 D`.