Q5 of 284 Page 256

An object 60 cm from a lens gives a virtual image at a distance of 20 cm in front of the lens. What is the focal length of the lens? Is the lens converging or diverging? Give reasons for your answer.

u = -60 cm

v = -20 cm


Using lens formula on solving, we get


Focal length = -30 cm


The lens is diverging as the focal length is negative.


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