**Effective mode volume** — For an optical fiber, the effective mode volume is the square of the product of the diameter of the near field pattern and the sine of the radiation angle of the far field pattern. The diameter of the near field radiation pattern is defined here… … Wikipedia

**effective pitch ratio** — Basic propeller characteristics represented by the formula V/nd, where V is air speed, n is propeller RPM, and d is diameter. Pitch ratio is the ratio of the geometric pitch, or other specified pitch, of a propeller to the diameter of the… … Aviation dictionary

**effective plug diameter** — n. the dimension obtained by adding the root depth of a key cut to the length of its corresponding bottom pin which establishes a perfect shear line. This will not necessarily be the same as the actual plug diameter … Locksmith dictionary

**effective aperture** — noun : the diameter of the entrance pupil of an optical system; specifically : the apparent diameter of the diaphragm opening in a camera lens as seen through the front of the lens … Useful english dictionary

**effective roll diameter** — Смотри катающий диаметр валка … Энциклопедический словарь по металлургии

**Electric effective resistance** — is the parameter of a passive two pole electric circuit or its element, which is equal to the relation of the effective power, which is absorbing in this element, to the square of the effective value of an electric current in it. Electric… … Wikipedia

**Terminal ballistics** — Terminal ballistics, a sub field of ballistics, is the study of the behavior of a projectile when it hits its target. It is often referred to as stopping power when dealing with human or other living targets. Terminal ballistics is as relevant… … Wikipedia

**Difference between train and tram rails** — A railroad or railway is a track where the vehicle travels over two parallel steel bars, called rails. The rails support and guide the wheels of the vehicles, which are traditionally either trains and trams. Modern light rail is a relatively new… … Wikipedia

**Noro–Frenkel law of corresponding states** — The Noro–Frenkel law of corresponding states is an equation in thermodynamics that describes the critical temperature of the liquid gas transition T as a function of the range of the attractive potential R. It states that, all short ranged… … Wikipedia

**Debye–Hückel equation** — The Debye–Hückel equation and Debye–Hückel limiting law, were derived by Peter Debye and Erich Hückel, who developed a theory with which to calculate activity coefficients of electrolyte solutions.[1] Activities, rather than concentrations, are… … Wikipedia