If a polaroid is kept in the path of a uniformly unpolarised light ,the intensity of the transmitted light to the intensity of the light ,when the polaroid is not kept in its path,is

When an unpolarised light intensity I_0 is incident on a polarising sheet ,the intensity of the light which does not get transmitted is

Two polarised are placed at 90^@ to each other and the intensity of transmitted light is zero. What will be the intensity of transmitted light, when one or more polaroids is placed between these two bisecting the angle between them? Take intensity of unpolarised light as I_0 ?

Can our eye distinguish polarised light from unpolarised light?

Three polaroids are placed insuch a manner that the third polaroid is crossed with the first.When a beam of unpolarised light of intenstiy 24 W m^(-2) falls on the first polaroid,the intensity of light reduces to 3W m^(-2) on emerging fromo the thrid polariod.Find the angle between the trnasmission axes of the second and third polaroid.

State one factaor which determines the intensity of light in the phton picture of light?

Does the thresold frequency depend on intensity of light?