Electrodynamics Classes

Oberlin College Physics 411

Classes taught and recorded in Fall 2020

This World Wide Web page written by Dan Styer, Oberlin College Department of Physics and Astronomy;
last major update 7 December 2020; formating revisions 2 December 2021.

"Griffiths" means David J. Griffiths, Introduction to Electrodynamics, fourth edition (2012).

Class 1.
Discussion of syllabus. Electrostatics and Magnetostatics. Faraday's Law, Maxwell Equations. Electric and magnetic potential energy.
(Griffiths chapter 7.)

Class 2.

Class 3.
What is a Vector?; Geometrical definitions of divergence and curl.

Class 4.
Geometrical significance of vector identities. Conservation of charge and the Maxwell equations. Magnetic monopoles.

Class 5.
Local conservation of energy; Poynting vector. Energy flowing into a resistor.

Class 6.
Mark Heald's "Electrostatics of a Circuit" problem. Feynman disk and angular momentum conservation.

Class 7.
Maxwell stress tensor.

Class 8.
One-dimensional waves (e.g. on a string). d'Alembert's solution.

Class 9.
Electromagnetic waves, in vacuum and in media. The many, various, and diverse phenomena of physics.

Class 10.
Potentials and gauges.

Class 11.
Lorenz gauge. Retarded solution for potentials and fields. Lienard-Wiechert potentials.

Class 12.
Uniformly moving source charge (cat whiskers). Radiation from a good swift kick. Simulations.

Class 13.
Electric dipole radiation. Blue sky. Red sunsets. Polarized sky.

Classes 14 - 15.
Space and time in special relativity.

Class 16.
Energy and momentum in special relativity. Four-current density.

Class 17.
What is mass? Gravitational and inertial mass. Operational definitions.
For more on these topics, see pages 20 to 25 of Notes for Mechanics and Relativity and the document Measuring Time in Meters.

Class 18.
Four-tensors, symmetic and antisymmetric. Electromagnetic field transformation. Maxwell equations in relativistic notation.

Class 19.
Stress-energy tensor.

Class 20.