Question

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion (A): Propagation of light through an optical fibre is due to total internal reflection taking place at the core-cladding interface

Reason (R) : Refractive index of the material of the core of the optical fibre is greater than that of air.

In the light of the above statements, choose the correct answer from the options given below

• A. Both (A) and (R) are true and (R) is the correct explanation of (A)
• B. Both (A) and (R) are true but (R) is not the correct explanation of (A)
• C. (A) is true and (R) is false
• D. (A) is false and (R) is true

Answer 1

Answer: (B)

Both (A) and (R) are true but (R) is not the correct explanation of (A)

Answer 2

Answer (b) Both (A) and (R) are true but (R) is not the correct explanation of (A)

Assertion (A): Propagation of light through an optical fibre is due to total internal reflection taking place at the core-cladding interface (correct)

Reason (R) : Refractive index of the material of the core of the optical fibre is greater than that of air. (True but not correct explanation)