
As given here, the pass axis of polaroids A and B are inclined at angle of 90º with each other. Another polaroid Cis placed at angle of 45∘with respect to A and B.
Therefore, intensity of light after falling on polaroid A,IA=2I0
Intensity of light after falling on polaroid C,IC=IAcos245∘=2I0cos245∘=4I0
Intensity of light after falling on polaroid B,IB=ICcos245∘=4I0cos245∘=8I0