Question

The core refractive index should be lesser than the cladding refractive index for a coaxial cable. State True/False

(a) True

(b) False

I got this question during an internship interview.

Enquiry is from Refractive Index and Numerical Aperture in section EM Wave Propagation of Electromagnetic Theory

Answer 1

The correct answer is (b) False

For explanation: The light should pass through the core region only, for effective transmission. When light passes through cladding, losses will occur, as cladding is meant for protection. Thus core refractive index must be greater than the cladding refractive index.