$A$ beam of light both reflects and refracts at the surface between air and glass. The refractive index of the glass is $1.4$. If the refracted and the reflected rays are perpendicular to each other,then the angle of incidence in the air is

Explain the polarisation of light by reflection,state Brewster's law,and derive its formula.

Choose the correct statement from the following. Brewster's angle for a transparent medium is

Unpolarised red light is incident on the surface of a lake at an incident angle $\theta_{R}$. An observer seeing the light reflected from the water surface through a polariser notices that on rotating the polariser,the intensity of light drops to zero at a certain orientation. The red light is replaced by unpolarised blue light. The observer sees the same effect with reflected blue light at an incident angle $\theta_{B}$. Then,

Consider a tank made of glass (refractive index $1.5$) with a thick bottom. It is filled with a liquid of refractive index $\mu$. $A$ student finds that,irrespective of what the incident angle $i$ (see figure) is for a beam of light entering the liquid,the light reflected from the liquid-glass interface is never completely polarized. For this to happen,the minimum value of $\mu$ is

The angle of incidence at which reflected light is totally polarized for reflection from air to glass (refractive index $n$) is: