question_answer

A light ray falls on a rectangular glass slab as shown. The index of refraction of the glass, if total internal reflection is to occur at the vertical face, is

A) \[\sqrt{3/2}\]

B)        \[\frac{(\sqrt{3}+1)}{2}\]

C)  \[\frac{(\sqrt{2}+1)}{2}\]         

D)        \[\sqrt{5}/2\]