An object is to be seen through a simple microscope of power `10 D`. Where should an object be placed to produce maximum angular magnification ? Least distance of distinct vision is `25 cm`.

Answer

`-7.1 cm`

Explanation

Angular magnification is maximum, whrn fianl image is formed at the least distinct vision.
`:. V = - 25 cm, f = (100)/(P) = (100)/(10) = 10 cm, u = ?`
From `(1)/(v) - (1)/(u) = (1)/(f)`
`(1)/(u) = (1)/(v) - (1)/(f) = (1)/(-25) - (1)/(10) = (-7)/(50)`
`u = -(50)/(7) = - 7.1 cm`