basic concepts of magnetism, including magnetic fields, magnetic poles, and

electromagnets. I also discuss the ultimate subatomic source of magnetic force

in the phenomenon of electric spin, and explain how this leads to the different

types of magnetic materials: ferromagnets, paramagnets, and diamagnets. I

conclude with some applications of electromagnetism, including electric

generators and motors, transformers, and a brief discussion of Maxwell's

equations. Recommended prelistening is Episode 43: Electric Forces and

Fields.