Question

A mirror magnifies the image twice and has a focal length 20cm. If it forms a real image find the distance of object from the mirror.

Answer 1

Explanation:

Hello

Since, magnification(m)=2

=> 2=-v/u

=> v=-2u

For Mirror,

1/f = 1/v + 1/u

=> 1/(-20) = 1/(-2u) + 1/u

=> 1/20 = 1/2u

=>2u=20

=> u=10 cm