Light from a point source placed at the bottom of a rectuangular glass slab of thikness 5 cm is internally reflected by the upper surface and a circle of radius 8 cm is formed at the bottom. Find the R.I. of glass.

Light from a point source placed at the bottom of a rectangular glass slab of thickness 5 cm is internally reflected by the upper surface and a circle of radius 8 cm is formed at the bottom. Find the refractive index of glass.

An ink dot on a sheet of paper is viewed from above a distance of 50 cm. By what distance would the ink dot appear to be raised if it is viewed through a glass slab of thickness 15 cm held parallel to the appear? Given refractive index of glass = 1.5.

A luminous point source is placed at a depth of 30 cm in a source containing a liquid of refractive index 1.25. From the source light rays are being emitted in all directions. The rays which are refracted from the upper surface of the liquid form a circle. Calculate the radius of the circle.