B EM Radiation Amplitude: Is Peak Related to Intensity?

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Electromagnetic radiation consists of sinusoidal electric and magnetic fields, with intensity defined as Power Flux Density (PFD) in watts per square meter (W/m2). The relationship between the RMS amplitudes of these fields and PFD is established through the intrinsic impedance of the medium, which is 377 Ohms for free space. For peak amplitudes, the PFD is halved compared to RMS values. The equations PFD = E^2 / R and PFD = R H^2 illustrate the connection between electric field (E), magnetic field (H), and intensity. Understanding these relationships is crucial for analyzing electromagnetic radiation properties.
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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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