Question

A light ray enters a glass slab at exactly 90⁰. Its angle of refraction is​

Answer 1

Answer:

When the angle of incidence in water reaches a certain critical value, the refracted ray lies along the boundary, having an angle of refraction of 90-degrees. This angle of incidence is known as the critical angle; it is the largest angle of incidence for which refraction can still occur.

angle of refraction is zero.

Explanation: