EM Radiation Amplitude: Is Peak Related to Intensity?

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jeremyfiennes
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Electromagnetic radiation is propagating sinusoidal electric and magnetic fields. Are the peak amplitudes of these fields in any way related to the radiation's other parameters, e.g. its instensity?
 
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jeremyfiennes said:
Electromagnetic radiation is propagating sinusoidal electric and magnetic fields. Are the peak amplitudes of these fields in any way related to the radiation's other parameters, e.g. its instensity?
Intensity is Power Flux Density, expressed in W/m2. The RMS amplitudes of the electric and magnetic fields are related to PFD in the following way, where R is the intrinsic impedance of the medium, 377 Ohms for free space:-
PFD = E^2 /R
PFD = R H^2
R = E/H
If using peak amplitudes rather than RMS, the PFD will be halved.
 
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