Electric & Magnetic Fields Out of Phase: Why?

[Shailesh Pincha]

Why can't we have an Electromagnetic wave in which the Electric Field and Magentic Field aren't in phase?

 

[jasonRF]

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

 

[tech99]

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.

 

[jasonRF]

Is the 45 degrees for a wave propagating inside the conductor? Thank you.

Yes.

 

[ElectricKitchen]

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.)

 

[jasonRF]

See chapter 2 of
http://eceweb1.rutgers.edu/~orfanidi/ewa/

Many textbooks (and probably online notes) cover this material.

jason