Question

A point light source is kept in front of a convex
mirror at a distance of 40 cm. The focal length
of the mirror is 40 cm. Find the position of
image.
​

Answer 1

Object distance   u=−40 cm

Focal length   f=40 cm

Using mirror  formula :   v1+u1=f1

Or    v1+(−40)1=(40)1

We get   v=20 cm