A small object is placed at a distance of `3.6cm` from a magnifier of focal length `4cm`.
(a) Find the position of the image.
(b) Final linear magnification.
(c ) Find the angualr magnification.

Explanation

(a) `u =- 3.6 cm, f = 4 cm, v = ?`
`(1)/(v) - (1)/(u) = (1)/(f)`
`(1)/(v) - (1)/(-3.6) = (1)/(4) rArr (1)/(v) = (1)/(4) - (1)/(3.6) = (0.9 - 1)/(3.6)`
`v =- 36 cm`
(b) Linear magnification `= (v)/(u) = (-36)/(-3.6) = 10`
`(c ) m = (D)/(u)`
`= (25)/(3.6) = 6.94`