As shown in the figure,three identical polaroids $P_1$,$P_2$,and $P_3$ are placed one after another. The pass axis of $P_2$ and $P_3$ are inclined at angles of $60^{\circ}$ and $90^{\circ}$ with respect to the axis of $P_1$. The source $S$ has an intensity of $256 \text{ W/m}^2$. The intensity of light at point $O$ is $........... \text{ W/m}^2$.

$A$ polaroid $(I)$ is placed in front of a monochromatic source. Another polaroid $(II)$ is placed in front of this polaroid $(I)$ and rotated until no light passes. $A$ third polaroid $(III)$ is now placed in between $(I)$ and $(II)$. In this case,will light emerge from $(II)$? Explain.

An unpolarised beam of intensity $I_{0}$ falls on a polaroid. The intensity of the emergent light is

Two polaroids $A$ and $B$ are placed in such a way that the pass-axes of the polaroids are perpendicular to each other. Now, another polaroid $C$ is placed between $A$ and $B$, bisecting the angle between them. If the intensity of unpolarised light is $I_0$, then the intensity of the transmitted light after passing through polaroid $B$ will be:

$A$ $20 \ cm$ length of a certain solution causes right-handed rotation of $38^{\circ}$. $A$ $30 \ cm$ length of another solution causes left-handed rotation of $24^{\circ}$. The optical rotation caused by a $30 \ cm$ length of a mixture of the above solutions in the volume ratio $1:2$ is

The wave property of electrons implies that they will show diffraction effects. Davisson and Germer demonstrated this by diffracting electrons from crystals. The law governing the diffraction from a crystal is obtained by requiring that electron waves reflected from the planes of atoms in a crystal interfere constructively. Which of the following phenomena establishes the transverse nature of light?