Question

An object is placed at a distance of 10 cm from a convex mirror of focal length 15 cm. Find the position and nature of the image.

Answer 1

Given, u=-10 cm, f=+15 cm,v=?

From mirror formula, 1/f=1/v+1/u

or 1/v=1/f=1/u

=1/v=1/15=1/(-10)=1/15+1/10=(2+3)/30

or  v=30/5=+6 cm

That is image is formed at a distance of 6 cm from the mirror behind it. The image is erect and virtual.