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When an object is at distance x and y fr...

When an object is at distance x and y from a lens, a real image and a virtual image is formed respectively having same magnification. The focal length of the lens is

Text Solution

Verified by Experts

Magnification `m=f/(f+u)`
[use sig convention in this formula]
According to the question
`m_1=-m_2 implies (f/(f-mu_1))=-(f/(f-mu_2))implies f=(mu_1+mu_2)/2`
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