Question

A ray of light is incident at an angle i from dense to rare medium. The reflected and refracted rays are mutually perpendicular. The angle of reflection and refraction are r and r' respectively. Find the critical angle.

Answer 1

Q.2 (AIIMS)

What should be the maximum acceptance angle at the air-core interface of an optical fibre if \(\sf n_1\) and \(\sf n_2\) are the refractive indices of the core and cladding.

Answer 2

first of all, I don't see why they've separately given \(i \) and \(r\) when \(i = r\).

Answer 3

Just to trick..

Answer 4

Wait, so if we get an answer in terms of \(r\), then it can also be represented in terms of \(i\). That's weird.

Answer 5

\[90 - r + 90 - r' = 90\]\[\boxed{r+r' = 90}\]