TABLE OF CONTENTS Warren B.Boast
Deceased. Formerly Anson Marston Distinguished Professor
Emeritus of Electrical Engineering, lowa State University;
Fellow, Institute of Electrical and Electronics Engineers
Harry W.Hale
Professor Emeritus of Electrical Engineering and Computer
Engineering, lowa State University; Senior Member, Institute of
Electrical and Electronics Engineers
Edwin C.Jones, Jr.
Professor of Electrical Engineering and Computer Engineering,
lowa State University; Fellow, Institute ofElectrical and
Electronics Engineers
Alvin L.Day
Associate Professor of Industrial and Manufacturing Systems
Engineering, lowa State University; Senior Member, Institute of
Electrical and Electronics Engineers
Definition of Electric Circuit. An electric circuit is a collection of electrical devices and components connected together for the purpose of processing information or energy in electrical form. An electric circuit may be described mathematically by ordinary differential equations, which may be linear or nonlinear and which may or may not be time-varying. The practical effect of this restriction is that the physical dimensions are small compared to the wavelength of any electrical signals. Many devices and systems use circuits in their design.
Electric Charge. In circuit theory, we postulate the existence of an indivisible unit of charge. There are two kinds of charge, called negative and positive charge. The negatively charged particle is called an electron. Positive charges may be atoms that have lost electrons, called ions; in crystalline structures, electron deficiencies, called holes, act as positively charged particles. In the International System of Units (SI), the unit of charge...
