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Question
An object is held 20 cm away from a converging lens of focal length 10 cm. Find the position of the image formed.
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Solution
Given:Converging lens, f = 10 cm and u = -20cm
`1/f = 1/v - 1/u`
`∴ 1/v = 1/f + 1/u`
`-> 1/v = 1/10 + 1/(-20) = 1/10 - 1/20`
`-> 1/v = 1/(20 cm)`
∴ v = 20 cm
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