We illustrate the use of Maxwell's term in Ampere's law and also the conservation laws of electromagnetic theory. First, we outline the conservation laws for energy and linear momentum which often appear in textbooks of electromagnetism, and then we show how these conservation laws can be extended to the conservation law for angular momentum and to the relativistic conservation law involving the center of energy. Next we treat the traditional example of charging a parallel-plate capacitor but explore a number of energy-conservation aspects and variations which are not usually found in textbooks. Finally, we discuss the charging of spherical conductors where we can illustrate the use of Maxwell's term and can provide non-trivial examples of three of the four conservation laws.

Topics
Energy conservation, Electromagnetism, Electric currents, Electrostatics, Magnetic fields, Maxwell equations, Newtonian mechanics, Electrodynamics, Special relativity, Educational aids
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2019
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