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

A diverging beam of light from a point source S having divergence angl

1.	A diverging beam of light from a point source S having divergence angle a falls symmetrically on a glass slab as shown. The angles of incidences of the two extreme rays are equal. IF the thickness of the glass slab is t and its refractive index is n, then the divergence angle of the emergent beam is
Answer» Solution :Divergence angle will remain unchanged because in case of a glass SLAB EVERY emergent ray is parallel to the incident ray. However, the rays are displaced slightly TOWARDS OUTER side. (In the figure `OA\|\|BC\|\| and OD\|\|EF)`