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Question
A convex lens forms an inverted image of size same as that of the object which is placed at a distance 60 cm in front of the lens. Find:
- The position of the image, and
- The focal length of the lens.
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Solution
The resulting image is flipped and of the same size.
(a) The distance between an object and a lens is the same for an image.
As u = -60 cm
∴ v = 60 cm
i.e., position of image v = 60 cm
(b) 2f = 60
f = `60/2`
f = 30 cm
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