Which of the following statement(s) is /are correct?
I) A Polaroid consists of long chain molecules aligned in a particular direction
II) Electric vectors along the direction of the aligned molecule in a Polaroid gets absorbed
III)An unpolarised light wave is incident on Polaroid, then it will get linearly polarized.

A Polaroid consists of long-chain molecules aligned in a particular direction. When a Polaroid is placed in between the path of the light, the electric vectors which are parallel to the pass-axis of the polaroid pass through it. Even if the polaroid is rotated, there would be other electric vectors which pass through it. So, the intensity of light does not change irrespective of the orientation of pass-axis of the polaroid.