Light waves can be polarized if they are...

Three polarising sheets are placed co-axially. The pass axes of polaroids $2$ and $3$ make angles of $30^{\circ}$ and $90^{\circ}$ respectively with the pass axis of polaroid $1$. If $I_0$ is the intensity of unpolarised light entering sheet $1$,what is the intensity of the light emerging from sheet $3$? $(\cos 30^{\circ}=\sqrt{3} / 2, \cos 90^{\circ}=0, \cos 60^{\circ}=1 / 2)$

Two polaroids are oriented with their planes perpendicular to incident light and their transmission axes making an angle of $30^{\circ}$ with each other. What fraction of the incident unpolarised light is transmitted? (Express as a percentage)

An unpolarized light beam of intensity $I_0$ is incident on a polarizer $A$ and then passed through a second polarizer $B$. If the principal plane of polarizer $B$ makes an angle of $45^\circ$ with respect to polarizer $A$,the intensity of the emerging light will be ........

When an unpolarized light of intensity $I_{0}$ is incident on a polarizing sheet, the intensity of the light which does not get transmitted is

Four polaroids are placed such that the optic axis of each is inclined at an angle of $30^{\circ}$ with the optic axis of the preceding one. If unpolarised light of intensity $I_0$ falls on the first polaroid,the intensity of light transmitted from the fourth polaroid is $[\cos 30^{\circ} = \sqrt{3} / 2]$.