One thing I have learned in a long life: that all our science, measured against
reality, is primitive and childlike—and yet is the most precious thing we have.
Electromagnetics (EM) may be regarded as the study of the interactions between electric
charges at rest and in motion. It entails the analysis, synthesis, physical interpretation, and
application of electric and magnetic fields.
is a branch of physics or electrical engineering in which
electric and magnetic phenomena are studied.
EM principles find applications in various allied disciplines such as microwaves, an-
tennas, electric machines, satellite communications, bioelectromagnetics, plasmas, nuclear
research, fiber optics, electromagnetic interference and compatibility, electromechanical
energy conversion, radar meteorology," and remote sensing.
In physical medicine, for
example, EM power, either in the form of shortwaves or microwaves, is used to heat deep
tissues and to stimulate certain physiological responses in order to relieve certain patho-
logical conditions. EM fields are used in induction heaters for melting, forging, annealing,
surface hardening, and soldering operations. Dielectric heating equipment uses shortwaves
to join or seal thin sheets of plastic materials. EM energy offers many new and exciting
possibilities in agriculture. It is used, for example, to change vegetable taste by reducing
EM devices include transformers, electric relays, radio/TV, telephone, electric motors,
transmission lines, waveguides, antennas, optical fibers, radars, and lasers. The design of
these devices requires thorough knowledge of the laws and principles of EM.
For numerous applications of electrostatics, see J. M. Crowley,
Fundamentals of Applied Electro-
New York: John Wiley & Sons, 1986.
For other areas of applications of EM, see, for example, D. Teplitz, ed.,
Electromagnetism: Paths to
New York: Plenum Press, 1982.