Malus's Law - Practice Questions & MCQ

Two beams, A and B, of plane-polarized light with mutually perpendicular planes of polarization are seen through a polaroid. From the position when beam A has maximum intensity (and beam B has zero intensity), a rotation of polaroid through 30⁰ makes the two beams appear equally bright. If the initial intensities of the two beams are I_A and I_B respectively, then   equal :

When an unpolarized light of intensity is incident on a polarizing sheet, the intensity of the light that does not get transmitted is

A plane polarized light is incident on a polariser with its pass axis making angle θ with x-axis, as shown in the figure. At four different values of θ, θ= , , and , the observed intensities are same. What is the angle between the direction of polarization and x-axis ?

Two Polaroids P₁ and P₂ are placed with their axis perpendicular to each other. Unpolarised light I₀ is incident on P₁. A third polaroid P₃ is kept in between P₁ and P₂ such that its axis makes an angle 45° with that of P₁ . The intensity of transmitted light through P₂ is:

A beam of un-polarised light of intensity I₀  is passed through a Polaroid A and then through another Polaroid B which is oriented so that its principal plane makes an angle of 45⁰ relative to that of A. The intensity of the emergent light is :