JEE PHYSICS MCQ: RAY OPTICS

1 Medium

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Understanding +4 | -1

Assertion: Propagation of light through an optical fibre is due to total internal reflection taking place at the core-clade interface.
Reason: Refractive index of the material of the core of the optical fibre is greater than that of air.

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Correct option: B

Both Assertion and Reason are true but Reason is not the correct explanation of Assertion

Option B (Both Assertion and Reason are true but Reason is not the correct explanation of Assertion) is correct because total internal reflection requires the core to have a higher refractive index than the cladding, not air.

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