question_answer

Abeam of unpolarised light of intensity L is passed through a polaroidAand 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

A) \[{{I}_{0}}\]

B) \[{{I}_{0}}/2\]  

C) \[{{I}_{0}}/4\]

D) \[{{I}_{0}}/8\]