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Science Physics Electromagnetism

Electromagnetism

Electrodynamics

Electromagnetic radiation

Electrical circuits

Absorption (electromagnetic radiation)

Way in which the energy of a photon is taken up by matter; physical process of absorbing light, while absorbance does not always measure absorption: it measures attenuation (of transmitted radiant power)

Absorption band

Range on the electromagnetic spectrum which are characteristic of a certain transition from initial to final state in a substance

Product of RMS voltage and RMS current in an AC electrical system

Alternating current

Electric current which periodically reverses direction

Ampère's circuital law

Concept in classical electromagnetism

Ampère's force law

Antiferromagnetism

Regular pattern of magnetic moment ordering

Biot–Savart law

Law of classical electromagnetism

Electromagnetic radiation produced by the deceleration of a charged particle when deflected by another charged particle

Vessel filled with a superheated transparent liquid

Ability of a body to store an electrical charge

Electric charge per volume, length or area

Classical electromagnetism

Branch of theoretical physics that studies consequences of the electromagnetic forces between electric charges and currents

Compton scattering

Scattering of photons off charged particles

Pair of electrons (or other fermions) bound together at low temperatures in a certain manner which is responsible for superconductivity as described in the BCS theory

Fundamental physical law of electromagnetism

Current density

Electric current per area of cross section

Cyclotron radiation

Ordinary, weak, repulsive magnetism that all materials possess

Electrically insulating substance able to be polarized by an applied electric field

Electromagnetic phenomenon

Unidirectional flow of electric charge

Displacement current

Physical quantity in electromagnetism

Loops of electrical current induced within conductors by a changing magnetic field

Electric charge

Electromagnetic property of matter

Electric current

Flow of electric charge

Electric dipole moment

Vector physical quantity measuring the separation of positive and negative electrical charges within a system

Electric displacement field

Vector field related to displacement current and flux density

Physical field surrounding an electric charge

Measure of electric field through surface

Electric potential

Line integral of the electric field

Electric potential energy

Potential energy that results from conservative Coulomb forces

The rate per unit of time at which electrical energy is transferred by an electric circuit

Electric susceptibility

Degree of polarization

Electrical conductor

Object or material which allows the flow of electric charge with little energy loss

Electrical impedance

The opposition of a circuit to a current when a voltage is applied

Electrical network

Assemblage of connected electrical elements

Electrical reactance

A circuit element's opposition to changes in current due to its inductance or capacitance

Electrical resistance and conductance

Opposition to the passage of an electric current

Electrical resistivity and conductivity

Measure of a substance's ability to resist or conduct electric current

Physical phenomena associated with the presence and flow of electric charge

Type of magnet in which the magnetic field is produced by the flow of electric current

Electromagnetic field

Electric and magnetic fields produced by moving charged objects

Electromagnetic four-potential

Relativistic vector field

Electromagnetic induction

Production of voltage by a varying magnetic field

Electromagnetic induction

Production of voltage by a varying magnetic field

Electromagnetic radiation

Form of energy emitted and absorbed by particles which are charged which shows wave-like behavior as it travels through space

Electromagnetic spectrum

Entire range of frequencies of electromagnetic radiation

Electromagnetic wave equation

Partial differential equation used in physics

Electromotive force

Electrical action produced by a non-electrical source

Study of still or slow electric charges

Evanescent field

Oscillating electric and/or magnetic field that does not propagate as an electromagnetic wave but whose energy is spatially concentrated in the vicinity of the source

Type of magnetic phenomenon

Physical phenomenon

Emission of light by a substance that has absorbed light

Gain (electronics)

Ability of a circuit to increase the power or amplitude of a signal

Penetrating form of electromagnetic radiation

Foundational law of electromagnetism relating electric field and charge distributions

Gauss's law for magnetism

Foundational law of classical magnetism

Ground (electricity)

Reference point in an electrical circuit from which voltages are measured

Production of a voltage difference across an electrical conductor

High-temperature superconductivity

Superconductive behavior at temperatures much higher than absolute zero

Property of electrical conductors

Form of electromagnetic radiation

Insulator (electricity)

Material that does not conduct an electric current

Areal density of incoming radiant flux

Kirchhoff's circuit laws

Two equalities that deal with the current and potential difference

Gives the total power radiated by an accelerating, nonrelativistic point charge

Electromagnetic phenomena where changing magnetic fields induce currents with opposing fields

Electromagnetic radiation in or near visible spectrum

Force acting on charged particles in electric and magnetic fields

Lorenz gauge condition

Symmetry condition in special relativity

Material or object that produces a magnetic field

Magnetic dipole

A magnetic dipole is the limit of either a closed loop of electric current

Surface integral of the magnetic flux density

Magnetic moment

Physical quantity; measured in ampere square metre

Magnetic monopole

Hypothetical particle with one magnetic pole

Magnetic susceptibility

Measure of how much a material will become magnetized in an applied magnetic field

Class of physical phenomena

Physical quantity, density of magnetic moment per volume

Magnetohydrodynamics

Study of the magnetic properties of electrically conducting fluids

Branch of physics concerned with magnetic behavior in systems with steady electric currents

Maxwell's equations

Equations describing classical electromagnetism

Materials engineered to have properties that have not yet been found in nature

Electromagnetic radiation with wavelengths from 1 m to 1 mm

Near and far field

Regarding radioantennas

Negative-index metamaterial

Metamaterials whose refractive index for an electromagnetic wave has a negative value over some frequency range

Nonlinear metamaterial

Law according to which the current through a conductor between two points is directly proportional to the voltage across the two points

Oil drop experiment

Experiment to measure elementary electric charge

Weak, attractive magnetism possessed by most elements and some compounds

Permeability (electromagnetism)

Measure of the ability of a material to support the formation of a magnetic field within itself

Physical quantity, measure of the resistance to the electric field

Photoelectric effect

Emission of electrons when light hits a material

Photonic metamaterial

Type of electromagnetic metamaterial

Single, negligibly-sized object from which light, sound, energy, etc. emanates

Polarization density

Vector field describing the density of electric dipole moments in a dielectric material

Poynting vector

Measure of directional electromagnetic energy flux

Physical quantity in radiometry

Measure of radiant energy over time

Radiative transfer

Energy transfer in the form of electromagnetic radiation

Radio Wave 96.5

Radio station in Blackpool

Techniques for measuring electromagnetic radiation

Propagation delay of EM radiation (light)

Material that has electrical conductivity intermediate to that of a conductor and an insulator

Spectral density

Relative importance of certain frequencies in a composite signal

Spontaneous magnetization

Sudden appearance of magnetic order in cold substances

Static electricity

Imbalance of electric charges within or on the surface of a material

Superconductivity

Electrical conductivity with exactly zero resistance

Synchrotron radiation

Electromagnetic radiation emitted when charged particles are accelerated radially

Terahertz radiation

Range 300-3000 GHz of the electromagnetic spectrum

Transverse mode

Electromagnetic wave with oscillations perpendicular to the direction of travel

Tunable metamaterial

Ultraviolet (disambiguation)

Topics referred to by the same term

Visible spectrum

Portion of the electromagnetic spectrum that is visible to the human eye

Difference in electric potential between two points in space

Waveguide (radio frequency)

Hollow metal pipe used to carry radio waves

Form of short-wavelength electromagnetic radiation