The path of a ray of light coming from air passing thro

The path of a ray of light coming from air passing thro
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The path of a ray of light coming from air passing through a rectangular glass slab traced by four students are shown as A, B, C and D in figure. Which one of them is correct?

A.

B.

C.

D.

Please scroll down to see the correct answer and solution guide.

Right Answer is: B

SOLUTION

At first face of glass slab, the light ray enters from air to glass (rarer to denser medium). Hence, the light ray bends towards the normal at first face of glass slab. At second face of glass slab, the light ray enters from glass to air (denser to rarer medium). Hence, it bends away from the normal at the second face of glass slab.
Thus, the emergent ray from glass slab is parallel to incident ray, but slightly displaced with respect to incident ray.