Question

Discuss refraction through a glass slab and show that the emergent ray is parallel to the incident ray but displaced.

Answer 1

When a light ray passes obliquely through a rectangular glass slab, it refracts twice,once on entering and once on leaving the slab. The emergent ray is parallel to the incident ray but remains laterally displaced due to refraction. This displacement depends on the thickness of the slab and angle of incidence.