A beam of unpolarised light of intensity `I_0` is passed through a polaroidA and then through another polaroid B which is oriented so that its principal plane makes an angle of `45^circ` relative to that of A. The intensity of the emergent light is

Options

A. `I_0`
B. `(I_0)/(2)`
C. `(I_0)/(4)`
D. `(I_0)/(8)`

Answer

C

Explanation

Relation between intensities `I-r=((I_0)/(2))cos^2(45^circ)=(I_0)/(2)xx(1)/(2)=(I_0)/(4)`