Re: magnetic field

100% wrote:
Tom Roberts wrote:
A field has no "speed". _Changes_ in the magnetic field propagate with
speed c relative to locally-inertial frames.

right, but if we take it in term of force, than acceleration,
integrating once then we get speed and a constant

Force is not acceleration. They can be related in some/many cases by the equations of motion, but they are not the same. "Integrating" force does not give speed. In Newtonian mechanics:
\integral f . dl = work {f and dl are 3-vectors}
\integral f dt = impulse

And, of course, the magnetic field is not force, either.


is it wrong to associate a speed ta tha pathlines of
tha magnetic field?

The magnetic field has no "pathlines", and the magnetic field has no "speed".


Tom Roberts tjroberts@xxxxxxxxxx
.