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The energy of EM radiation can be described by the Poynting vectorS=ExB(insert conversion factor for cgs, MKS, etc).

For a traveling EM wave, what happens to the instantaneous value of S when E and B are max as compared to when E and B are 0?

Alternatively, how is the energy of the EM radiation shared between E and B with both E and B having maximum and zero values at the same instant of time for a plane wave?

Thank you for your input.

WRG

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# Instantaneous poynting vector for EM radiation

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