How is the Relative Angle Between Two Polarizers Determined?

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The discussion centers on determining the relative angle between two polarizers when unpolarized light passes through them. Given that the intensity of light after the second polarizer is 1/4 I0, the angle between the polarizers is established to be 45 degrees. The relevant equation used to derive this result is I = I0 cos²(θ), where θ is the angle between the polarizers. Participants seek clarification on the relationship between intensity and the angle, confirming that it is not linear but follows the cosine squared relationship. The conversation concludes with an acknowledgment of the clarity provided by the equations discussed.
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A beam of unpolarized light, with intensity I0, goes through two polarizers. If the intensity of the light coming out of the second polarizer is 1/4 I0 what is the relative angle between the two polarizers??

----I know the answer is 45 degrees---
but if anyone could explain how?? Thanks!
 
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tica86 said:
A beam of unpolarized light, with intensity I0, goes through two polarizers. If the intensity of the light coming out of the second polarizer is 1/4 I0 what is the relative angle between the two polarizers??

----I know the answer is 45 degrees---
but if anyone could explain how?? Thanks!

Can you post the Relevant Equations? Is it a linear relationship between crossed polarizers and intensity, or does it follow a different relationship?
 


berkeman said:
can you post the relevant equations? Is it a linear relationship between crossed polarizers and intensity, or does it follow a different relationship?

i1=1/2i0
i2=1/4i0
 


tica86 said:
i1=1/2i0
i2=1/4i0

Well okay then. We're all done here. That makes everything obvious. Thanks.
 


berkeman said:
Well okay then. We're all done here. That makes everything obvious. Thanks.

I=I0cos^2theta
 
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