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?
If 'i' is the angle of incidence and x is the refracted angle then at the second surface also x will be the angle of incidence by alternate angle property and hence, angle 'i' will be the emergent angle which is equal to the incidence angle. So these two rays will be parallel. Hence, the angle between incident ray and emergent ray = 0∘. In rectangular glass slab, the direction of emerging light is same as that of incident light.