The purpose of this supplement is to present the basic material needed to understand the operation of simple DC motors. This is intended to be used as the reference material for the linear and DC motors lectures in EE301, as this material is not covered in the text.

Before introducing electric motors, it is helpful to define electric motors. In simplest terms, electric motors are machines which convert electrical energy into mechanical energy. A few examples of familiar electric motors include motors that raise and lower car windows, rotate ceiling fans, and spin CDs and DVDs.

A linear motor is a basic easy-to-understand electrical motor. Although the linear design is not useful for most practical electrical motors, the concepts that are learned here are useful in understanding rotating DC motors. This section will introduce or review: some basic concepts of magnets and magnetic flux, the Lorentz force law, Faraday's law, and
then the simple DC linear motor.