On Jun 28, 11:57=A0am, blackhead <larryhar...@[EMAIL PROTECTED]
> wrote:
> There seems to be quite a few people in this newsgroup who, when they
> can, keep bringing up the subject of E and B not causing one another,
> contrary to what is outlined in most text books. That Jefimenko was
> the first to see this, via his equations which express E and B in
> terms of their sources at retarded time t'. E =A0and B are functions of
> the charge density Rho(r', t'), d/dt Rho(r', t'), current density
> J(r', t'), d/dt J((r', t'), and R
>
> where R =3D r - r', retarded time t' =3D t - R/c, r is the field point
at
> time t, r' is the position of the source at time t':
>
> http://en.wikipedia.org/wiki/Jefimenko's_equations
>
> On the other hand, the Lienard-Wiechert equations were derived over
> 100 years ago and, in my view, go further by exploiting the fact that
> most EM problems consist of charge moving continuously through space.
> The equations thus end up vastly simplified giving E and B just in
> terms of the position of the charge and observation point; velocity
> and acceleration of the moving charge:
>
> E_ =3D e[ (n_ - B_)( 1 - B^2) / k^3R^2 + n_ x (( n_ - B_) x a_) /
> c^2K^3R
>
> B_ =3D [_n] X E_
>
> Where:
> e =3D charge on moving source
> c =3D speed of light
> _ is a vector
> R_ is the position vector from where the charge was to the field point
> n_ =3D R_/R,
> _B =3D u_/ c
> K =3D 1 - B_ dot n_
>
> I don't see any advantages to using Jefimenko's over those of Lienard-
> Wiechert and would be interested in your views.
>
> Cheers.
See my response on June 29 in another thread:
http://groups.google.com/group/sci.physics.electromag/browse_frm/thread/434=
57040bd467476?hl=3Den
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