Question

The image formed by a convex mirror of focal length 30cm is a quarter of the object. What is the distance of the object from the mirror

Answer 1

hii mate !!

↪the mirror formula is given as

1/f = (1/v) + (1/u)  (1)

❄here

f = focal length = 30cm

v = image distance 

u = object distance

↪we are given that

hi = ho/4

or

hi / ho = 1/4

hi = image height

ho = object height

↪now as

hi / ho = -v/u = 1/4

we get

v = -u/4

 ↪ so, using this in eq. (1), we get

1/30 = -4/u + 1/u

or

1/30 = -3/u

❄thus, the object distance will be

u = -90 cm

hope it helps !!☺☺

Answer 2

The image formed by the convex mirror is