Polarized light: Where did the magnetic field go?

AI Thread Summary
Diagrams of polarized light often depict an electric field entering a polarizing filter and only an electric field exiting, raising questions about the fate of the magnetic field. The magnetic field associated with the light remains present and is perpendicular to both the electric field and the direction of propagation. It does not get eliminated by the filter; instead, it passes through unchanged as long as the corresponding electric field can also pass through. The confusion may stem from representations that focus solely on the electric field of different polarization states. Understanding this relationship clarifies the behavior of light as it interacts with polarizing filters.
gauss44
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Many of the diagrams of polarized light seem to show light with an electric field and a magnetic field approaching the polarizing filter, but only an electric field coming out of the filter. Where did the magnetic field* go? Does a filter that produces plane polarized light somehow eliminate the magnetic field? Does the magnetic field just pass through the filter unchanged, so long as the corresponding electric field is able to pass through?

*The magnetic field associated with the light that makes it through the filter.

(This question was inspired by an MCAT review book. I am not a student. I am studying for the medical school admissions test, to hopefully make it into medical school.)
 
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It is still present and is perpendicular to the electric field and the direction of propagation. Perhaps your diagram was showing the electric field of different polarization states?
 
Drakkith said:
It is still present and is perpendicular to the electric field and the direction of propagation. Perhaps your diagram was showing the electric field of different polarization states?

That must have been it.
 

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