Question

Derive an expression for the acceptance angle numerical aperture of
an optical fibre​

Answer 1

Answer:

If outer medium is air, then n3 = 1. The acceptance angle ia becomes, Light can have any angle of incidence from 0 to ia with the normal at the end of the optical fibre forming a conical shape called acceptance cone. In the equation (6), the term (n3 sin ia) is called numerical aperture NA of the optical fibre.

Explanation:

MARK AS BRAINILIEST ☺️✌️