﻿ Two objects A and B when placed in turn in front of a concave mirror of focal length 7.5 cm, give images of equal size. If A is three times the size ofB and is placed 30 cm from the mirror, what is the distance of B from the mirror?  : Kaysons Education

# Two Objects A and B when Placed In Turn In Front Of A Concave Mirror Of Focal Length 7.5 Cm, Give Images Of Equal Size. If A is Three Times The Size OfB and Is Placed 30 Cm From The Mirror, What Is The Distance Of B from The Mirror?

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## Question

### Solution

Correct option is

15 cm

It is given that f = –7.5 cm and uA = –30 cm. Thus

Which gives

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