Electric & Magnetic Fields Out of Phase: Why?

AI Thread Summary
Electromagnetic waves can exhibit electric and magnetic fields that are out of phase depending on the medium. In free space or ideal loss-less dielectrics, these fields remain in phase. However, in real dielectrics with losses, the fields can become out of phase, while in good conductors, they can be 45 degrees out of phase. Analytical solutions for this behavior can be found in various textbooks and resources. Understanding these phase relationships is crucial for applications in electromagnetics.
Shailesh Pincha
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Why can't we have an Electromagnetic wave in which the Electric Field and Magentic Field aren't in phase?
 
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You can - it depends on the medium in which the wave is propagating. In free space or an idealized loss-less dielectric they are in phase. Once you add a little loss in the dielectric (as all real dielectrics have) then the fields are no longer exactly in phase. In a good conductor the electric and magnetic fields are 45 degrees out of phase.

jason
 
In a good conductor the electric and magnetic fields are 45 degrees out of phase.

jason
Is the 45 degrees for a wave propagating inside the conductor? Thank you.
 
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Is the 45 degrees for a wave propagating inside the conductor? Thank you.
Yes.
 
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Is there an analytical solution to show that E and M fields in a perfect conductor are out of phase by 45 degrees? (I can handle the calculus.)
 

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