Electric and magnetic fields in matter

thumb|upright=1.35|alt=Lighting strikes on a city at night|Electricity is invisible, but it can yield visually observable phenomena, shown here with the flash of lightning and various forms of [[electric light in the buildings.]]

thumb|A polarised dielectric material (orange), between two metal plates

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

product of the electric current through a loop, the area enclosed by the loop and the unit vector perpendicular to the loop

thumb|Pyrolytic carbon has one of the largest diamagnetic constants of any room temperature material. Here a pyrolytic carbon sheet is levitated by its repulsion from the strong magnetic field of [[neodymium magnets]]

thumb|Liquid oxygen (blue) can be suspended between the poles of a strong magnet as a result of its paramagnetism.

Magnetostatics is the study of magnetic fields in systems where the currents are steady (not changing with time). It is the magnetic analogue of electrostatics, where the charges are stationary. The magnetization need not be static; the equations of magnetostatics can be used to predict fast magnetic switching events that occur on time scales of nanoseconds or less. Magnetostatics is even a good approximation when the currents are not static – as long as the currents do not alternate rapidly. Magnetostatics is widely used in applications of micromagnetics such as models of magnetic stora

production of a voltage difference across an electrical conductor in a magnetic field

thumb|A dielectric medium showing orientation of charged particles creating polarization effects. Such a medium can have a lower ratio of electric flux to charge (more permittivity) than empty space.

In classical electromagnetism, magnetization is the vector field that expresses the density of permanent or induced magnetic dipole moments in a magnetic material. Accordingly, physicists and engineers usually define magnetization as the quantity of magnetic moment per unit volume. It is represented by a pseudovector M. Magnetization can be compared to electric polarization, which is the measure of the corresponding response of a material to an electric field in electrostatics.

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

vector field related to displacement current and flux density

ratio of permittivity to the electric constant

in physics, the ratio of magnetomotive force to magnetic flux; the magnetic analogue of electrical resistance

In physics and materials science, ferroelectricity is the property of certain materials that exhibit a spontaneous electric polarization—an internal electric alignment that arises naturally without an external source. This polarization can be reversed when an external electric field is applied.

physical quantity

closed loop path containing a magnetic flux

degree of polarization

relation of magnetization to applied magnetic field and temperature

Polarizability usually refers to the tendency of matter, when subjected to an electric field, to acquire an electric dipole moment in proportion to that applied field. It is a property of particles with an electric charge. When subject to an electric field, the negatively charged electrons and positively charged atomic nuclei are subject to opposite forces and undergo charge separation. Polarizability is responsible for a material's dielectric constant and, at high (optical) frequencies, its refractive index.

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

differential equation parameter in thermal physics

measuring dielectric properties of a medium for differing frequencies

characterizes how quickly an electron can move through a metal or semiconductor, when pulled by an electric field

describes the scattering of conduction electrons in a metal due to magnetic impurities, resulting in a characteristic change in electrical resistivity with temperature

relations connecting the real and imaginary parts of any complex function that is analytic in the upper half-plane

In electromagnetism, electrostriction is a property of all electrical non-conductor or dielectrics. Electrostriction causes these materials to change their shape under the application of an electric field. It is the dual property to magnetostriction.

thumb|Electromigration (red arrow) is due to the momentum transfer from the electrons moving in a wire Electromigration is the transport of material caused by the gradual movement of the ions in a conductor due to the momentum transfer between conducting electrons and diffusing metal atoms. The effect is important in applications where high direct current densities are used, such as in microelectronics and related structures. As the structure size in electronics such as integrated circuits (ICs) decreases, the practical significance of this effect increases.

optical phenomenon

thumb|Lodestone attracting some iron nails thumb|Lodestone in the National Gem and Mineral Collection#Hall of Geology, Gems, and Minerals|Hall of Gems of the [[Smithsonian]] thumb|Lodestone attracting small bits of iron Lodestones are naturally magnetized pieces of the mineral magnetite. They are naturally occurring magnets, which can attract iron. The property of magnetism was first discovered in antiquity through lodestones. Pieces of lodestone, suspended so they could turn, were the first magnetic compasses, and their importance to early navigation is indicated by the name lodestone, which

an abstract boundary in reciprocal space useful for predicting the thermal, electrical, magnetic, and optical properties of metals, semimetals, and doped semiconductors

radius of the circular movement of an electrically charged particle in a magnetic field

quantum phenomenon

relation between two physical quantities that is specific to a material or substance

magnetic effect in insulators between ferromagnets

solid-state electrical conductor which conducts due to the movement of ions

material through which electromagnetic waves propagate

intrinsic magnetic dipole moment of neutrons

principle in the function of solid-state electronic devices

an electron in a static and uniform magnetic field will move in a circle due to the Lorentz force

In electromagnetics and materials science, antiferroelectricity is a physical property of certain materials. It is closely related to ferroelectricity; the relation between antiferroelectricity and ferroelectricity is analogous to the relation between antiferromagnetism and ferromagnetism.

Permeance, in general, is the degree to which a material admits a flow of matter or energy. Permeance is usually represented by a curly capital P: .

theorem

heating using radio waves

a phenomenon related to the movement of ions in a magnetic field

temperature change of a material under an electric field

a noncontact variant of atomic force microscopy

Flexoelectricity is a property of a dielectric material where there is coupling between electrical polarization and a strain gradient. This phenomenon is closely related to piezoelectricity, but while piezoelectricity refers to polarization due to uniform strain, flexoelectricity specifically involves polarization due to strain that varies from point to point in the material. This nonuniform strain breaks centrosymmetry, meaning that unlike in piezoelectricity, flexoelectric effects occur in both centrosymmetric and asymmetric crystal structures. This property is not the same as ferroelasticit

Rate of change of the electric field of an atomic nucleus

The name electrospray is used for an apparatus that employs electricity to disperse a liquid or for the fine aerosol resulting from this process. High voltage is applied to a liquid supplied through an emitter (usually a glass or metallic capillary). Ideally the liquid reaching the emitter tip forms a Taylor cone, which emits a liquid jet through its apex. Varicose waves on the surface of the jet lead to the formation of small and highly charged liquid droplets, which are radially dispersed due to Coulomb repulsion.

in physics: electromagnetic momentum within dielectric media

pertinent to space weather conditions

Formula in optics

occurs in bilayers (or multilayers) of magnetic materials where the hard magnetization behavior of an antiferromagnetic thin film causes a shift in the soft magnetization curve of a ferromagnetic film