1.

The near point of a person suffering from hypermetropia is 75 cm. Calculate the focal length and power of the lens required to enable him to read the newspaper which is kept at 25 cm from the eye.

Answer»

Solution :`u=-25cm`
`v=-75 cm`
`(1)/(v)-(1)/(u)=(1)/(F)`
`(1)/(-75)-(1)/(-25)=(1)/(f)rArr (1)/(-75)+(1)/(25)=(1)/(f)`
`(2)/(75)=(1)/(f)`
`rArr""f=(75)/(2)=37.5cm`
`"So,P"=(100)/(37.5)`
`=2.6D`


Discussion

No Comment Found

Related InterviewSolutions