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Question
If a magnification of, –1 is to be obtained by using a converging lens of focal length 12 cm, then the object must be placed:
(a) within 12 cm
(b) at 24 cm
(c) at 6 cm
(d) beyond 24 cm
Solution
At 24 cm
For an object placed at a distance of 2F from a convex lens, the size of the image so formed is equal to the size of the object.
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