Assertion (A): Propagation of light through a | vedclass

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(B) The assertion $(A)$ is true because optical fibres work on the principle of total internal reflection $(TIR)$, which occurs when light travels fro

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

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(B) The assertion $(A)$ is true because optical fibres work on the principle of total internal reflection $(TIR)$, which occurs when light travels from a denser medium (core) to a rarer medium (cladding) at an angle of incidence greater than the critical angle.The reason $(R)$ states that the refractive index of the core is greater than that of air. While it is true that the core has a higher refractive index than air, the condition for $TIR$ in an optical fibre is that the refractive index of the core $(n_1)$ must be greater than the refractive index of the cladding $(n_2)$, not necessarily air.Therefore, while both statements are factually correct, the reason $(R)$ does not explain why $TIR$ occurs at the core-clad interface. The correct explanation would involve the relationship between the core and the cladding refractive indices.

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

Similar Questions

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Optical fibres are related with

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