geoscixyz / em

Electromagnetic methods in geophysics - open educational resources.
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wavelengh equation needs to be double checked #538

Open jiajiasun opened 5 years ago

jiajiasun commented 5 years ago

The equation for the wavelength of a plane wave in the frequency domain on this webpage (https://em.geosci.xyz/content/maxwell1_fundamentals/harmonic_planewaves_homogeneous/wavelength.html#harmonic-planewaves-homogeneous-wavelength-formula) does not seem right.

The wavelength is defined by 2X \pi/wavenumber, where wavenumber, in this case, would be either alpha or beta. Therefore, wavelength is 2X \pi/ \beta = 2 X pi X sqrt(2/(\omega \mu \sigma)).

It looks like a factor of 2Xpi is missing from the equation on the above webpage. Could anyone please double check?

ralfschaa commented 5 years ago

Yes, I also stumbled over this -- double checked with Stratton, cf. page 274 (eq. 40) and p. 277 (eq. 54)