SPINNING ELECTROMAGNETIC FIELDS

The aim of this site is to analyse and describe some properties of classical electromagnetic fields. Topics of particular interest include charged and uncharged spinning fields and the fields and interaction of spinning and orbiting charges. Theoretical analysis is based on classical electromagnetic theory and frequent use has been made of Maple 6, a symbolic computation computer program. To assist in understanding the mathematics many field plots and graphs have been included and it is hoped that this together with detailed descriptions will ensure that readers who wish to ignore the maths can still understand the effects being described. A few working Maple program listings will also be included on the site although I’m afraid you must have your own Maple software to run them. It is intended to add further web pages and topics as time permits.

Site Contents (Pages marked with an asterisk (*) are mainly mathematical):-

__Uncharged Resonant Spinning Electromagnetic Fields__

Uncharged
Resonant Spinning Electromagnetic Fields (640KB)**.**

Describes both stationary and spinning cavity resonant modes. General description and overview of evidence for spinning fields.

*Spherical Cavity Field
Equations for Stationary and Spinning Modes (313KB)**.**

This page also shows how the conventional cavity resonator equations actually describe both spinning and stationary fields.

*Cylindrical Cavity Field Equations for Stationary and Spinning Modes (390KB).

Gives the stationary and spinning field equations but with limited explanation as this is mostly the same as for the spherical cavities as described above.

*Tables of Spherical Cavity Resonant Modes (53KB).

Contains tables showing the lowest frequency allowed modes and formulae for their resonant frequencies.

*Tables of Cylindrical Cavity Resonant Modes (59KB).

Contains tables showing the lowest frequency allowed modes and formulae for their resonant frequencies.

Experiment to Produce Spinning Electromagnetic Fields in a Cylindrical Cavity (507KB).

Describes one way to produce spinning fields and covers some of the practical difficulties encountered.

** **Photographs of Spinning Electromagnetic
Field Cavity Experiment (190KB).

Shows three photographs of experimental set-up used.

** **

__The Fields of Electric Point Charges__

Part 1 – Basic Theory.
(290KB).

Contains an introduction to some of the standard textbook theory of the fields of charges when stationary or moving in a straight line. Outlines the retarded potential technique used in Maple computer program 1. A simple example of manually calculating the induction field at the centre of the orbit of a relativistic orbiting charge and a field plot for an oscillating charge are included.

Part 2 – Relativistic
Circular Orbits (490KB).

Examines the electric and magnetic fields along the diameter of the charge orbit in detail. Also investigates the field immediately outside the charge orbit. Shows that for a stationary observer the electric field magnitude at the centre and far side of the orbit of a relativistic charge is no greater than it would be for a stationary charge and is usually slightly less. (although the field angle is different).

__Maple 6 Computer Programs__

*Program
1 -To Calculate the Classical Fields of a Number of Relativistic Charges
(290KB).

Also works with slow moving and stationary charges.

__Miscellaneous__

Contains an attempt to give a simple explanation of Maxwell’s equations.

__Site
technical content last updated__: 25^{th} March
2005.