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Easy
Question
An equiconcave lens has focal length 10 cm in air. The refractive index of the material of the lens is 1.5. What should be the refractive index of the medium on the other side of the lens so that the image of a real object placed at a distance 10 cm from the lens is formed at infinity?
- 1.8
- 2.5
- 2
- 3
The correct answer is: 2
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