2006 Handbooks

The theory of electromagnetism, one of the most successful and most widely applied theories of modern physics, describes the properties and behaviour of electric and magnetic fields and their interaction with charged matter. This theory underlies all of modern optics, telecommunication and electrical engineering, and has played an important role in furthering our understanding of the fundamental forces of nature. In this unit, the basic laws of electromagnetism are introduced, and their important consequences and applications in electrostatics, magnetostatics and electrodynamics are studied. It is also shown how these laws can be re-expressed in terms of the more powerful mathematical language of vector calculus, which leads to the derivation of Maxwell's equations, the equations that give a fully unified description of electromagnetism. The overwhelming success of these equations in describing all manner of electromagnetic phenomena, in particular the propagation of light, played an important role in inspiring Einstein to formulate his special theory of relativity, which changed forever our concepts of space and time. The unit concludes with an introduction to this theory, and looks at such topics as the Lorentz transformation, length contraction, time dilation and the equivalence of mass and energy.