Wave Optics

As shown in the figure, a ray AB of unpolarized light enters from water of refractive index nw=4/3 into a medium of refractive index np=4/ 3 after passing through a glass plate of refractive index ng=1.5 and a layer of water. At a particular incident angle i the reflected ray CD is polarized in the direction as shown in the figure. The value of i (in degrees) is: [figure]

A solid glass sphere of refractive index n= 3 and radius R contains a spherical air cavity of radius R2, as shown in the figure. A very thin glass layer is present at the point O so that the air cavity (refractive index n=1) remains inside the glass sphere. An unpolarized, unidirectional and monochromatic light source S emits a light ray from a point inside the glass sphere towards the periphery of the glass sphere. If the light is reflected from the point O and is fully polarized, then the angle of incidence at the inner surface of the glass sphere is . The value of is [figure]