Question

why is the emergent ray parallel to incident ray in refraction of glass slab?

Answer 1

Refraction through a glass slab. So, the incident ray is parallel to theemergent ray but it is laterally displaced from it. Question: A ray oflight travelling in air falls on the surface of a transparent glass slab. The ray makes and angle of 45∘ with the normal to the surface.

Answer 2

In case of a glass slab,the incident ray after refraction from the glass slab bends towards the normal and travels inside the glass slab in a straight line and suffers another refraction due to which the incident ray is parallel to emergent ray.

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