Question

A horizontal beam of vertically polarized light of intensity 42.0 W/m2 is sent through two polarizing sheets. The polarizing direction of the first is at 26.0° to the vertical, and that of the second is horizontal. What is the intensity of the light transmitted by the pair of sheets?

Answer 1

When a light passes through a polariser, then the intensity of the light which comes out of the polarizer is:

Where: is the angle between incoming polarized light and the axis of polarizer

Step1) When the vertical palarised light passes through first polarizing Sheet:

Note: = 26 deg = 0.45 radians

But now this light is polarised at an angle of 26 deg from the vertical direction

Therefore, in the next case: wil be: 90-26 = 64 deg = 1.12 radians

and final intensity after passing through the second polarising sheet is:

.... thats your answer!!

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