ElektromagnetismusTheorie

Electromagnetism is a branch of physics that studies the interaction between electric charges and magnetic fields and the forces that arise from these interactions. It describes how moving charges generate magnetic fields and how changing magnetic and electric fields induce electric currents and electromagnetic waves.

Historically, phenomena of electricity and magnetism were studied separately until the 19th century, when James Clerk Maxwell formulated a set of equations that describe the relationship between electric field, magnetic field, charge distributions, and currents. Maxwell's equations show that electric and magnetic fields propagate as electromagnetic waves at the speed of light, unifying optics with electricity and magnetism.

The theory treats the electromagnetic field as a single entity with electric field E and magnetic field B; in vacuum and matter, Maxwell's equations determine field behavior and radiation. The fundamental equations include Gauss's law, Gauss's law for magnetism, Faraday's law of induction, and the Ampère-Maxwell law. In quantum terms, light can be described as photons, quanta of the electromagnetic field.

Applications include electric power generation and distribution, motors and generators, transformers, wireless communication, radar, and optical devices such as lenses and lasers.

Electromagnetism is one of the four fundamental interactions in nature, alongside gravity, the weak, and strong nuclear forces. It is described by classical electromagnetism at macroscopic scales and quantum electrodynamics in microscopic regimes.