Question

A 5 centimetre tall object is placed perpendicular to the principal axis of a convex lens of focal length 20cm is the distance of the object from the lens is 30 cm find the position ​

Answer 1

Answer: 60cm.

Explanation:

Using lens formula

1/v=1/f+1/u

Where

v=image distance

u = image distance

f=fiscal length

Object is left of lens so it is negative according to sign convention.

So,

1/v = -1/30 + 1/20

1/v = 1/60

V = 60 cms

Hope it helps...