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A cocave lens forms the image of an obje...

A cocave lens forms the image of an object such that the distance between the object and image is 10 cm and the magnification produced is 1/4. the focal length of the lens will be

A

22 cm

B

44 cm

C

10 cm

D

4.4 cm

Text Solution

Verified by Experts

The correct Answer is:
A

`v/u=1/4andu-v=10" "thereforeu=40/3andv=10/3`
now `1/v-1/u=1/for1/(-10//3)-1/(-40//3)=1/f" "thereforef=-6.67cm`
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