Calculating Electric Field Amplitude of Transmitted Light

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To calculate the electric field amplitude of transmitted light through a polarizing sheet, the initial intensity of unpolarized light is 30 watts/m^2, leading to a polarized intensity of 15 watts/m^2. The relationship between intensity and electric field is given by I = (E^2)/(μ₀c). The discussion highlights the need to relate the electric field amplitudes of the transmitted and incident light, ultimately simplifying the problem using the correct equations. The participants express frustration over the placement of questions in the textbook, indicating a common challenge in finding relevant information. Understanding the relationship between intensity and electric field is crucial for solving the problem effectively.
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Homework Statement



A beam of unpolarized light with intensity 30 watts/m^2 passes through a polarizing sheet. What is the electric field amplitude of the transmitted beam?

Homework Equations



Ia=Ipcos2\Theta
Ea=Epcos\Theta
Ip=Io/2

The Attempt at a Solution



I solved the first two equations for cos\Theta and set them equal to each other to get sqrt(Ia/Ip)=Ea/Ep

I know Io is 30, so Ip is 15

So then, I believe I should have sqrt(2)=Ea/Ep and I don't know how to just solve for one without the other...
 
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you need to know how the intensity of light is related to the electric field intensity. Look after in your textbook.

ehild
 
Ah, okay, so scrap all that and use I=(E2)/muoc

Thanks!

The book apparently likes to put questions at the end of random chapters!
 

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