Two polaroids A and B are placed in such a way that the pass-axis of polaroids are perpendicular to each other. Now, another polaroid C is placed between A and B bisecting angle between them. If intensity of unpolarised light is I 0 then intensity of transmitted light after passing through polaroid B will be :

Step-by-step solution

As given here, the pass axis of polaroids A and B are inclined at angle of 90 º with each other. Another polaroid C is placed at angle of 45 ° with respect to A and B . Therefore, intensity of light after falling on polaroid A ,   I A = I 0 2 Intensity of light after falling on polaroid C ,   I C = I A cos 2 45 ° = I 0 2 cos 2 45 ° = I 0 4 Intensity of light after falling on polaroid B ,   I B = I C cos 2 45 ° = I 0 4 cos 2 45 ° = I 0 8