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For a given lens, the magnification was ...

For a given lens, the magnification was found to be twice as large as when object was 0.15 m distant from it as when the distance was 0.2 m. The focal length of the lens is

A

1.5 m

B

0.20 m

C

0.10 m

D

0.05 m

Text Solution

Verified by Experts

The correct Answer is:
A
Here `m_(1) = 2m_(2)`
`(f)/(f-0.15)=2(f)/(f-0.20)`
2f - 0.30 = f - 0.02 , f = 0.10 m
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