effective oskarmand Fr.: effectif Actually in operation or in force; concrete; real. M.E., from L. effectivus "practical," from effect(us), p.p. of efficere, → effect + -ivus "-ive." Oskarmand, from oskar, → effect + -mand possession suffix. |
effective aperture dahâne-ye oskarmand Fr.: ouverture effective Of an antenna, the ratio of the extracted power by the antenna to the power per unit area (power density) in the incident wave. |
effective Eddington parameter pârâmun-e Eddington-e oskarmand Fr.: paramètre d'Eddington effectif The effective value of the → Eddington parameter in a non-homogeneous system (porous opacity). → effective; → Eddington limit; → parameter. |
effective focal length derâzâ-ye kânuni-ye oskarmand Fr.: longueur focale effective The focal length of an imaging system, which consists of several lenses or mirrors. → effective; → focal length. |
effective gravity gerâni-ye oskarmand Fr.: gravité effective In a → rotating star, the sum of the → gravity and the → centrifugal acceleration. The effective gravity is a function of the rotation velocity (Ω) and the → colatitude (θ). At the pole (θ = 0°) and the equator (θ = 90°) the effective gravity is radial. See also → total gravity. |
effective radius šo'â'-e oskarmand Fr.: rayon effectif Of a galaxy, the distance from its center within which half of the total luminosity is included. |
effective temperature damâ-ye oskarmand Fr.: température effective A measure of the surface temperature of a star derived from the total emitted energy, assuming that the star is a → blackbody emitter (→ Stefan-Boltzmann law, → Planck's radiation law). See also → brightness temperature; → color temperature. → effective; → temperature. |
effectiveness oskarmandi Fr.: effectivité The degree to which goals are achieved and the extent to which posed problems are solved. Compare → efficiency. |