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Question
A convex lens of focal length 8 cm forms a real image of the same size as the object. The distance between object and its image will be:
(a) 8 cm
(b) 16 cm
(c) 24 cm
(d) 32 cm
Solution
32 cm
A convex lens forms a real image at 2f on the right side of the lens. The size of the image is equal to that of the object if the object is placed at 2f.
∴ Distance between the image and the object =` 2f + 2f = 4f = 4xx 8 = 32 cm`
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