Q index dišan-e Q Fr.: indice Q In the Johnson → UBV system, a reddening-free parameter which is related to the → effective temperature of stars and thus provides a useful, but rough, discriminant for → spectral types. It is expressed as: Q = (U - B) - 0.72 (B - V). → index. |
quadrangle cahârgušé, cârguš Fr.: quadrilatère A two-dimensional figure that consists of four points connected by straight lines. Same as → tetragon; see also → quadrilateral. L.L. quadrangulum, noun use of neuter of L. quadrangulus, quadriangulus "four-cornered," from quadr- variant of quadri- before a vowel "four," akin to quattuor, → four, cognate with Pers. cahâr, as below; → angle. Cahârgušé, cârguš "four-cornered," from cahâr, câr "four," cognate with L. quattuor, → four, + gušé, guš "corner, angle;" Mid.Pers. gôšak "corner." |
Quadrans Muralis Cârakân Fr.: Quadrant An obsolete → constellation created by the French astronomer Jérôme Lalande in 1795. He named it such for the main astronomical instrument, that is → mural quadrant, he used. Quadrans Muralis was located between the constellations → Boötes and → Draco. The name disappeared from astronomical catalogs, but the → meteor shower→ Quadrantids has kept that name. |
quadrant cârakân Fr.: quadrant 1) A quarter of a circle; an arc of 90°. M.E., from L. quadrantem (nominative quadrans) "fourth part." Cârakân, from cârak + -ân. Cârak "quarter," literally "fourth, a fourth part of one," from câr, variant of cahâr, → four, cognate with L. quattuor, + -ak, contraction of yak "one," from Mid.Pers. êwak (Proto-Iranian *aiua-ka-); O.Pers. aiva- "one, alone;" Av. aēuua- "one, alone" (cf. Skt. éka- "one, alone, single;" Gk. oios "alone, lonely;" L. unus "one;" E. one); -ân nuance suffix. |
Quadrantids Cârakâniyân Fr.: Quadrantides An annual → meteor shower reaching a peak about 3 January and having its → radiant in the constellation → Boötes. From L. Quadrant-, from Quadrans Muralis , → mural quadrant. |
quadratic câruši Fr.: quadratique Of or relating to or resembling a → square. Quadratic, adj. of quadrate, from L. quadratus p.p. of quadrare "to make square." Câruši pertaining to câruš "square," from Av. caθruša- "four sides (of a four-sided figure)," from caθru- "four," Mod.Pers. cahâr, câr "four," cognate with L. quattuor, → four. |
quadratic equation hamugeš-e câruši Fr.: équation quadratique An equation with the general form of ax^{2} + bx +c = 0, in which the highest power of the unknown is the second power (square). |
quadratic formula disul-e câruši Fr.: formule quadratique A formula relating the unknown part of a → quadratic equation (the roots of the equation, x) to the known parts (a, b, and c): x = (-b± (b^{2} - 4ac)^{½}) / 2a. |
quadrature 1) cârušeš, câruši; 2) navadân, cârušeš Fr.: quadrature 1) General: The process of making something square; the act of squaring. From L. quadratura, from quadrat(us) p.p. of quadrare "to make square." 1) Cârušeš verbal noun of cârušidan "to square,"
from câruš "square," from Av. caθruša-,
→ quadratic. |
quadrature of the circle cârušeš-e parhun, ~ dâyeré Fr.: quadrature du cercle Constructing a square whose area equals that of a given circle. This was one of the three geometric problems of antiquity. It was finally proved to be an impossible problem when π was proven to be transcendental by Lindemann in 1882. Same as → squaring the circle. → quadrature; → circle. |
quadrilateral cahârbar (#), cârbar(#) Fr.: quadrilatère A plane figure bounded by four straight lines. From L. quadrilater(us) "four-sided," from L. quattuor, → four, + → lateral. |
quadruple cahârtâ (#), cahârtâyi (#) Fr.: quadruple Fourfold; consisting of four parts. M.E. from L. quadruplus, from quadru- + duple, from duplus, from du(o) "two" + -plus "fold." Cahârtâ, from cahâr, → four, cognate with L. quattuor, + tâ "fold, plait, ply; piece, part" (Mid.Pers. tâg "piece, part"). |
quadruple system râžmân-e cahârtâyi Fr.: système quadruple A stellar system consisting of four stars orbiting around a common → center of mass. |
quadrupolar cahârqotbé (#), cahârqotbe-yi (#) Fr.: quadrupolaire Of or pertaining to a → quadrupole, especially a → quadrupole moment. → quadrupole + -ar, → -al. |
quadrupole cahârqotbé (#) Fr.: quadrupôle A set of either two → electric dipoles or two → magnetic dipoles in close proximity to each other arranged with alternating polarities and acting as a single unit. Quadrupole interactions are much smaller than dipole interactions, but can allow transitions forbidden in dipole moment transitions. From L. quadru-, variant of quadri- "four" + → pole, on the model of → dipole. |
quadrupole anisotropy nâ-izogardi-ye cahârqotbé Fr.: anisotropie quadrupolaire The → anisotropy which is at the origin of the → cosmic microwave background polarization. The quadrupole anisotropy could arise from three types of perturbations: → scalar perturbation, → vector perturbation, and → tensor perturbation → quadrupole; → anisotropy. |
quadrupole lens adasi-ye cahârqotbé Fr.: lentille quadrupôle A device, consisting of four → electrodes or → magnetic poles arranged in alternating → polarity, that focuses a beam of → charged particles. → quadrupole; → lens. |
quadrupole moment gaštâvar-e cahârqotbé Fr.: moment quadrupolaire A quantity characterizing an electric charge distribution, determined by the product of the charge density, the second power of the distance from the origin, and a spherical harmonic over the charge distribution. → quadrupole; → moment. |
quake larzidan; larzé, larz Fr.: trembler; tremblement 1) To shake or tremble. M.E., from O.E. cwacian "to shake, tremble," of unknown origin. Larzidan, larz "to tremble, shiver," → seismo-. |
qualification cunâyeš Fr.: qualification 1) A quality, accomplishment, etc., that fits a person for some function,
office, or the like. |