Question

The image formed by a convex mirror of focal length `30 cm`. is a quarter of the object. What is the distance of the object from the mirror ?
A. 30 cm
B. 60 cm
C. 90 cm
D. 120 cm

Answer 1

Correct Answer - C
Given, `f=+30 cm` and `m=(1)/(4)`
Magnification, `m=(f)/(f-u)`
`therefore " " (30)/(30-u)=(1)/(4)`
`" " 30-u=120 rArr u =- 90 cm`