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electric field of moving charges

时间:04-05 整理:3721RD 点击:
Hi,

We know that stationary charges produce electric field and charges moving with constant velocity produces static magnetic field. But what is the electric field produced by charges moving with constant velocity?

I believe that as the position of the charges keep on changing, the electric field distribution changes. Since this distribution changes with time, this means that the Electric field is time-varying. A time-varying electric field must generate a magnetic field(generally, may or may not be time-varying) and this magnetic in this case is a non-varying, thus supporting the creation of static magnetic field by moving charges.

Is this stream of thought correct? Please reply...

Although I cannot grasp your entire thought, it makes me recall the static charge that develops in thunderclouds (usually positive polarity)...
and how free electrons form a corresponding 'pool' in the ground directly beneath,
and how the electrons travel at matching speed in order to stay beneath the cloud-borne positive charges.

I have not heard of experiments done to measure magnetic flux associated with lightningstorms.

The link below is a list of articles by Bill Beatty, whose concepts about electricity come from the attempt to delve deeper into its true (and inscrutable) nature.

ARTICLES ABOUT "ELECTRICITY" - William J. Beaty

http://amasci.com/ele-edu.html

Are you considering an infinite long strip with certain Coulomb/m charge that moves, or a situation where the charge density changes?

For the first case, the E-field doesn't change from the static situation, as you always "see" the same amount of charge. In the last case both E and H changes. From my head, the H-field is because of the length contraction (Lorentz).

Electric field of a moving charge travels along with that charge. Such moving charge will generate a magnetic field at a specific location as due to the Faraday induction law, at such location charge movement will cause a derivative of the electric field related to the dx, or, position change due to charge movement.
Only charges moving in a harmonic way (here and there) will generate an electromagnetic fields and waves.
Moving charges were utilized in linear accelerators and cathode-ray tubes where they traveled along a line and could interact with external electric and magnetic fields. Electric fields caused charge movements across a screen, magnetic fields an do the same, and if oriented along the charge moving line, they pulled the charges closer to the line (e.g. in klystrons, TWTs and BWOs)

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