JEE PHYSICS MCQ: RAY OPTICS

1 Medium

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Assertion: A concave mirror of focal length in air is used in a medium of refractive index 2 . Then the focal length of mirror in medium becomes double.

Reason: The radius of curvature of a mirror is double of the focal length.

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Correct option: D

If Assertion is false but Reason is true.

Option D is correct because the focal length of a mirror is independent of the surrounding medium, and the radius of curvature is indeed twice the focal length.

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