Question

is there any chance that angle of refraction is equal to 90°?​

Answer 1

Answer:

Angle of reflection can be 90° when:

1. Light moves from the denser to rarer medium.

2. The angle of incidence is equal to the critical angle for the given pair of media.

Eg. The critical angle for glass-air interface is 42° and for water-air interface is 49°.

Hope this helps you.