Question

An object is placed in front of a concave mirror of a concave mirror of focal length 20cm .The image formed is three times the size of the object. Calculate two possible distance of the object from the mirror.

Answer 1

Answer:

Explanation:f=-20 cm ho=hi/3

m=hi/ho=3    3=-v/u, -3u=v

by mirror formula

1/f=1/v+1/u   1/-20=1/-3u+1/u

-1/20=2/3u      u=-40/3

distance of object is 40/3 cm.