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

For a given lens, the magnification was found to be twice as large as

1.	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
Answer» 1.5 m 0.20 m 0.10 m 0.05 m Solution :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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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

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