An object is placed at a large distance in front of a convex mirror of radius of curvature 40 cm. How far is the image behind the mirror?

Answer

20 cm

Explanation

Here, `R = 40 cm, u = oo, v = ?`
As `1/u +(1)/(v) = (1)/(f) = 2/R, 1/(oo) + (1)/(v) = 2/ 40` or `v = 20 cm`.