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An Object is Held 20 Cm Away from a Converging Lens of Focal Length 10 Cm. Find the Position of the Image Formed. - Science and Technology 1

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प्रश्न

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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उत्तर

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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2016-2017 (March)

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