Light waves can be polarized if they are...

Two beams,$A$ and $B$,of plane polarized light with mutually perpendicular planes of polarization are seen through a polaroid. From the position when the beam $A$ has maximum intensity (and beam $B$ has zero intensity),a rotation of the polaroid through $30^{\circ}$ makes the two beams appear equally bright. If the initial intensities of the two beams are $I_A$ and $I_B$ respectively,then $\frac{I_A}{I_B} = $

The figure shows a glass plate placed vertically on a horizontal table. $A$ beam of unpolarised light falls on its surface at the polarising angle of $57^\circ$ with the normal. The electric vector in the reflected light on screen $S$ will vibrate with respect to the plane of incidence in a:

An unpolarised beam of light is incident on a group of three polarising sheets arranged such that the angle between the axes of any two adjacent sheets is $30^{\circ}$. The ratio of the intensities of polarised light emerging from the second and third sheets is

$A$ point source $S$ emits unpolarized light uniformly in all directions. At two points $A$ and $B$,the ratio $r = I_A / I_B$ of the intensities of light is $2$. If a set of two polaroids having $45^{\circ}$ angle between their pass-axes is placed just before point $B$,then the new value of $r$ will be.

Unpolarised light of intensity $32 \, W m^{-2}$ passes through a combination of three polaroids such that the pass axis of the last polaroid is perpendicular to that of the pass axis of the first polaroid. If the intensity of the emerging light is $3 \, W m^{-2}$,then the angle between the pass axis of the first two polaroids is $............ \, ^{\circ}$.