What was the initial polarization direction of the incident light?

AI Thread Summary
The discussion revolves around determining the initial polarization direction of incident light when it passes through two polarizers oriented at 40 degrees to each other, resulting in only 15% of the light transmitting through. The application of Malus's Law is suggested as the method to solve the problem. After calculations, the initial polarization angle is found to be approximately 59.6 degrees. Participants engage with the problem-solving process, confirming the approach and solution. The conversation highlights the importance of understanding polarizer interactions in optics.
xQuin
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Homework Statement


Two polarizers are oriented at 40deg to each other and plane-polarized light is incident on them. If only 15% of the light gets through both of them, what twas the initial polarization directon of the incident light?


Homework Equations





The Attempt at a Solution


I think it ha something to do with Malus's Law but I'm not sure exactly how
 
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welcome to pf!

hi xQuin! welcome to pf! :wink:

yes, assume that the angle of polarization to the first polarizer is θ …

how much goes through the first polarizer, and how much of that goes through the second?

show us what you get :smile:
 
Thanks tim, I applied the law twice and managed to get an answer of 59.6deg =D
 
looks good! :smile:
 
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