Unpolarized light falls on two polarizing sheets placed one after another. What should be the angle between the pass axes of the sheets so that the final transmitted light has one-fourth the intensity of the incident light?

Plane polarised light is passed through a polaroid. On viewing through the polaroid,we find that when the polaroid is given one complete rotation about the direction of the light,one of the following is observed:

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 $[\cos 30^{\circ} = \sqrt{3} / 2]$.

Choose the correct alternative regarding the polarisation of light.

$A$ $300 \, mm$ long tube contains $60 \, cm^3$ of a concentrated sugar solution. When placed in a polarimeter,it produces an optical rotation of $10^\circ$. If the specific rotation of sugar is $60^\circ$,calculate the amount of sugar in grams present in the tube.

An unpolarised light beam of intensity $2 I_{0}$ is passed through a polaroid $P$ and then through another polaroid $Q$ which is oriented in such a way that its passing axis makes an angle of $30^{\circ}$ relative to that of $P$. The intensity of the emergent light is.