Where should an object be placed in front of a convex lens to get a real image of the size of the object

Monjur Alahi

Where should an object be placed in front of a convex lens to get a real image of the size of the object

(a) At the principal focus of the lens (b) At twice the focal length
(c) At infinity
(d) Between the optical centre of the lens and its principal lens.


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Salim Ahmed Kawsar

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For real image of same size, the object must be placed at the distance 2f in front of convex lens, choice (b) is correct.

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