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Question
An object is 100 mm in front of a concave mirror which produces an upright (erect image). The radius of curvature of the mirror is ______.
Options
Less than 100 mm
Between 100 mm and 200 mm
Exactly 200 mm
More than 200 mm
Solution
An object is 100 mm in front of a concave mirror which produces an upright (erect image). The radius of curvature of the mirror is more than 200 mm.
Explanation:
The reason being, a concave mirror forms an erect image when an object is placed between the focus and the pole. Further, the radius of curvature is twice the distance between the focus and the pole. This gives a radius of curvature greater than 200mm.
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