A diverging beam of light from a point source S having divergence angle α, falls symmetrically on a glass slab as shown. The angles of incidence of the two extreme rays are equal. If the thickness of the glass slab is t and the refractive index n, then the divergence angle of the emergent beam is

Question

A diverging beam of light from a point source S having divergence angle α, falls symmetrically on a glass slab as shown. The angles of incidence of the two extreme rays are equal. If the thickness of the glass slab is t and the refractive index n, then the divergence angle of the emergent beam is (A) Zero (B) α (C)  sin -1(1 / n) (D) 2 sin -1(1 / n)

Tardigrade Admin · Accepted Answer

Since rays after passing through the glass slab just suffer lateral displacement hence we have angle between the emergent rays as α. <img class="img-fluid question-image" alt="image" src="https://cdn.tardigrade.in/img/question/physics/1850d1d39798f74a6b33453106cb0a3a-.png" />

Zero

$α$

$sin^{- 1} (1/ n)$

$2 sin^{- 1} (1/ n)$

Since rays after passing through the glass slab just suffer lateral displacement hence we have angle between the emergent rays as $α$ .

Zero

α

sin−1(1/n)

2sin−1(1/n)

Since rays after passing through the glass slab just suffer lateral displacement hence we have angle between the emergent rays as α.

$α$

$sin^{- 1} (1/ n)$

$2 sin^{- 1} (1/ n)$

Since rays after passing through the glass slab just suffer lateral displacement hence we have angle between the emergent rays as $α$ .