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General
Easy
Question
A object is placed at a distance of 15 cm from a convex lens of focal length 10 cm. On the other side of the lens, a convex mirror is placed at its focus such that the image formed by the combination coincides with the object itself. The focal length of the convex mirror is
- 20 cm
- 10 cm
- 15 cm
- 30 cm
The correct answer is: 10 cm
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