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Question
The focal length of a small concave mirror is 2.5 cm. In order to use this concave mirror as a dentist's mirror, the distance of tooth from the mirror should be:
(a) 2.5 cm
(b) 1.5 cm
(c) 4.5 cm
(d) 3.5 cm
Solution
1.5 cm
When an object is placed between the pole and the focus of a concave mirror, an enlarged image is formed.
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