An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

1) The physical phenomena arising from the behavior of → electrons and → protons that is caused by the → attraction of particles with opposite → charges and the → repulsion of particles with the same charge.
2) The → science of electric charges and → currents.
3) A → flow of electrons that is used to generate → light and → power electric devices.

From L. electrum "amber," from Gk. elektron "amber" + -ity a suffix used to form abstract nouns expressing state or condition.

Barq, Pers. term, used also in Ar. and Hebrew (barak "lightening"); variants in Pers.: varq, barx, balk, belak, bala; Lârestâni belak; Tabari, Lahijâni, Semnâni, Sorxeyi, Sangesari belk; Gilaki val; Lori beleyz; Kurd. bilese; Tokharian AB pâlk; Mid/Mod.Pers. bir "lightening," Mid.Pers. brâh "brilliance, splendour," br'z- "to shine, beam," Mod.Pers. barâz "beauty, grace, elegance;" Av. brāz- "to shine, beam; splendour," brazāiti "shines;" cf. Skt. bhrāj- "to shine, beam, sparkle," bhrajate "shines;" Gk. phlegein "to burn;" L. fulgere "to shine," fulmen "lightning," flagrare "to blaze, burn;" O.H.G. beraht "bright;" O.E. beorht "bright;" E. → bright; PIE base *bherəg-; *bhrēg- "to shine; white."

A property observed in certain materials characterized by the presence of a spontaneous electric polarization even in the absence of an external electric field. In the ferroelectric state the center of positive charge of the material does not coincide with the center of negative charge. This phenomenon is explained by spontaneous alignment of these permanent moments along the same direction. The term comes from the similarity with → ferromagnetism, but iron is not a ferroelectric. Ferroelectricity disappears above a critical temperature. Ferroelectric materials have been a fertile field for the study of → phase transitions.

→ ferro-; → electricity.

The total electric flux ψ out of an arbitrary closed surface in free space is equal to the net charge within the surface divided by the → permittivity. In differential form: ∇ . E = ρ/ε₀, where ρ is the → charge density and ε₀ the permittivity. The integral form of the law: ∫E . dS = Q/ε₀ (closed surface integral). This is one of the four → Maxwell's equations.

→ gauss; → law; → electricity.

The electricity produced by heat or temperature difference in a conductor.

→ thermo- + → electricity.