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somecelxis
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Homework Statement
Two pieces of polaroid are arranged so they are initially parallel . One of the polaroid is rotated until the intensity of the light beam from the two polaroid is 1/3 of its initial intensity . Calculate the angle turned thru the polaroid
Homework Equations
The Attempt at a Solution
i assume it's a non-polarised passing thru the first polaroid , then the second polaroid is rotated.
so i have Intensity after passing thru 1st polaroid (I 1 ) = 0.5 intensity of non-polarised (I 0)...
for light ray emerging from second polaroid = (I 2 ) = 0.5(I 0) ( (cos θ )^2) .finally i found out my θ = 35.3° the ans form the book is 54.7°
why i am wrong?
the initial light ray is polarised or non- polarised? how to determine it? it's not stated in the question...