Two polarizers are placed such that the angle between their transmission axes is $60^o$. If unpolarised light of intensity $I_0$ is incident on the first polarizer,then the transmitted intensity from the second polarizer will be

In a system of two crossed polarisers,it is found that the intensity of light from the second polariser is half of that from the first polariser. The angle between their pass axes is (in $^{\circ}$)

An unpolarized beam of intensity $2a^2$ passes through a thin polaroid. Assuming zero absorption in the polaroid,the intensity of emergent plane-polarized light is

$A$ system of three polarizers $P_1, P_2, P_3$ is set up such that the pass axis of $P_3$ is crossed with respect to that of $P_1$. The pass axis of $P_2$ is inclined at $60^{\circ}$ to the pass axis of $P_3$. When a beam of unpolarized light of intensity $I_0$ is incident on $P_1$,the intensity of light transmitted by the three polarizers is $I$. The ratio $(I_0/I)$ equals (nearly)

Three identical polaroids $P_1, P_2$, and $P_3$ are placed one after another. The pass axes 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 has an intensity $I_0$. The intensity of light finally coming out is

$A$ beam of unpolarized light passes through a tourmaline crystal $A$ and then it passes through a second tourmaline crystal $B$ oriented so that its principal plane is parallel to that of $A$. The intensity of emergent light is $I_0$. Now $B$ is rotated by $45^{\circ}$ about the ray. The emergent light will have intensity $(\cos 45^{\circ} = \frac{1}{\sqrt{2}})$.