Question

Why does a light ray incident on a rectangular glass slab immersed

in any medium emerges parallel to itself? Explain using a diagram.​

Answer 1

Answer:

This is why the ray emerges parallel to the incident ray on a rectangular glass slab. However, the light ray is shifted sideward slightly. When glass slab in immersed in any medium the interface AB(medium-glass) and CD glass medium are equal and opposite so, the emergent ray will always be parallel to the incident ray.