Q. A ray $R_{1}$ is incident on the plane surface of the glass slab (kept in air) of refractive index $2$ at an angle of incidence equal to the critical angle for this air glass system. The refracted ray $R_{2}$ undergoes partial reflection and refraction at the other surface. The angle (in degree) between reflected ray $R_{3}$ and the refracted ray $R_{4}$ at that surface is ?

845 161 Ray Optics and Optical Instruments Report Error

Answer: 105.00