Question

$\text{Statement 1}$ : On viewing the clear blue portion of the sky through a Calcite crystal, the intensity of transmitted light varies as the crystal is rotated.

$\text{Statement 2}$: The light coming from the sky is polarized due to the scattering of sunlight by particles in the atmosphere. The scattering is the largest for blue light.

• A. Statement $1$ is false and Statement $2$ is true.
• B. Both Statement $1$ and Statement $2$ are true, but Statement $2$ is not a correct explanation of Statement $1$.
• C. Statement $1$ is true and Statement $2$ is false.
• D. Both Statement $1$ and Statement $2$ are true, and the Statement $2$ is correct explanation of Statement $1$.

Answer 1

The correct option is D Both Statement $1$ and Statement $2$ are true, and the Statement $2$ is correct explanation of Statement $1$.

The light coming from the sky is polarized due to the scattering of sunlight by particles in the atmosphere.

The intensity of scattered light $\propto \frac{1}{{\lambda }^4}$, as the blue colour has a shorter wavelength than red, therefore, blue colour is scattered much more strongly. Thus, the Statement $2$ is true.

We know that when a polarized light is passed through a Polaroid its intensity will vary when the Polaroid will be rotated.
So, when the polarized light from the blue portion of the sky is passed through a Calcite crystal (a Polaroid), the intensity of this polarized light will certainly vary when the Polaroid is rotated.

Thus, Statement $1$ is true and Statement $2$ is the correct explanation for statement $1$.

Hence, option $\left(\text{A}\right)$ is correct.