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An object is kept 40 cm in front of a concave mirror whose focal length is 20 cm. The image formed will be

1. real, inverted and diminished
2. real, inverted and equal in size
3. real and upright
4. virtual and inverted

Correct answer: real, inverted and equal in size

Solution

With u = 40 cm and f = 20 cm, the object sits at the centre of curvature (2f). The image also forms at 2f: it is real, inverted and equal in size to the object.

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