The near point of a person is `50 cm` and the far point is `1.5m`. The spectacles required for reading purpose and for seeing distant objects are respectively

Options

A. `+2D,-(2)/(3)D`
B. `+(2)/(3)D,-2D`
C. `-2D,+(2)/(3)D`
D. `-(2)/(3)D,+2D`

Answer

A

Explanation

`(1)/(-50)-(1)/(-(25)) = (1)/(f)`
`(1)/(f) = (1)/(50) rArr P = (100)/(f(cm)) = (100)/(50) = 2D`
`(1)/(-250)- (1)/(oo) = (1)/(f')`
`f' =- 150cm rArr P = (100)/(-150)=- (2)/(3)D`