The intensity of incident unpolarized light on a polaroid is $I_1$ and the intensity of emergent polarized light from this polaroid is $I_2$. The relation between $I_1$ and $I_2$ is $.......$

For light of intensity $I_0$,a polaroid is placed at an angle of $45^\circ$. What will be the intensity of the light passing through the polaroid after polarization?

Which of the following statements indicates that light waves are transverse?

An unpolarised light of intensity $I$ is passed through two polaroids kept one after the other with their planes parallel to each other. The intensity of light emerging from the second polaroid is $\frac{I}{4}$. The angle between the pass axes of the polaroids is (in $^{\circ}$)

Statement-$1$: The blue part of the sky is clearly visible through a calcite crystal. The intensity of the transmitted light changes as the crystal is rotated.
Statement-$2$: Light from the sky is due to the scattering of sunlight by particles in the atmosphere.

Define unpolarized light and polarized light.