$A$ transparent medium shows a relationship between $\sin i$ and $\sin r$ as shown in the graph. If the speed of light in vacuum is $c$,the Brewster angle for the medium is: (in $^{\circ}$)

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

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

Critical angle for a certain medium is $\sin ^{-1}(0.6)$. The polarizing angle of that medium is

The angle of polarisation for any medium is $60^{\circ}$. What will be the critical angle for this medium?

$A$ person lives in a high-rise building at a height of $30 \ m$ on the bank of a river. Across the river is a well-lit tower of height $60 \ m$. When the person looks through a polarizer at an appropriate angle at light from the top of the tower reflecting from the river surface,he finds the intensity of light is least. If the refractive index of water is $\frac{4}{3}$,the width of the river is ...... $m$.