Electromagnetics

   

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      Electricity and magnetism practically affects all aspects of our life. The most spectacular natural manifestation of electricity is lightening, but without tiny electrical signals buzzing through our nervous system we would not be what we are, and without light (an electromagnetic wave) life on our planet would not be possible. Electromagnetic theory involves the macroscopic behaviour of electric charges in matter and vacuum. This behaviour can be accurately characterized by the Lorentz force law and Maxwell’s equations, which were derived from experiments showing how forces on charges depend on the relative locations and motions of other charges nearby.
      The electromagnetic field/theory is based on Maxwell's four equation of electromagnetism which acts as the four pillars of this field/theory. The theory of electromagnetism includes the introduction (i.e., the definition) of several fundamental concepts among which: Field and substance, electric charge, electric current, state quantities of electric and magnetic fields. Also, it contains the study of forces acting upon electric charge carriers in motion, laws and energy of electromagnetic field. Its implications are of fundamental importance in all of electrical engineering.

Electromagnetism 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, antennas, 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 pathological 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 acidity. 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.