Q8 of 12 Page 92

Solve the following examples.

An object kept 60 cm from a lens gives a virtual image 20 cm in front of the lens. What is the focal length of the lens? Is it a converging lens or diverging lens?

As per the question


The object distance is u=-60cm


Virtual image is v =-20cm



⇒


⇒ f= -30cm


From above we can conclude that as the focal length is negative it is diverging in nature and is a concave lens.


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