JEE PHYSICS MCQ: RAY OPTICS

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Assertion : In optical fibre, the diameter of the core is kept small.
Reason : This smaller diameter of the core ensures that the fibre should have incident angle more than the critical angle required for total internal reflection.

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Correct option: A

If both Assertion and Reason are true and the Reason is a correct explanation of the Assertion

Option A is correct because the smaller diameter of the core in optical fiber ensures the incident angle is greater than the critical angle for total internal reflection.

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