Useful english dictionary. 2012.
Rayleigh disc — /ˈreɪli dɪsk/ (say raylee disk) noun a small disc hung by a fine thread in the path of a soundwave so that the extent to which the disc is deflected is a measure of the intensity of the soundwave. {See Rayleigh criterion} …
Accretion disc — An accretion disc (or accretion disk) is a structure (often a circumstellar disk) formed by diffuse material in orbital motion around a central body. The central body is typically either a young star, a protostar, a white dwarf, a neutron star,… … Wikipedia
Optics — For the book by Sir Isaac Newton, see Opticks. Optical redirects here. For the musical artist, see Optical (artist). Optics includes study of dispersion of light. Optics is the branch of … Wikipedia
Angular resolution — describes the resolving power of any image forming device such as an optical or radio telescope, a microscope, a camera, or an eye. Definition of terms Resolving power is the ability of the components of an imaging device to measure the angular… … Wikipedia
electromagnetic radiation — Physics. radiation consisting of electromagnetic waves, including radio waves, infrared, visible light, ultraviolet, x rays, and gamma rays. [1950 55] * * * Energy propagated through free space or through a material medium in the form of… … Universalium
Airy disk — Computer generated image of an Airy disk. The gray scale intensities have been adjusted to enhance the brightness of the outer rings of the Airy pattern … Wikipedia
HD 189733 b — Planetbox begin name = HD 189733 b Planetbox image caption = An artist s impression of HD 189733 b about to block out its parent star.Planetbox star star = HD 189733 A constell = Vulpecula RA = RA|20|00|43.7133 DEC = DEC|+22|42|39.070 dist ly =… … Wikipedia
Scientific phenomena named after people — This is a list of scientific phenomena and concepts named after people (eponymous phenomena). For other lists of eponyms, see eponym. NOTOC A* Abderhalden ninhydrin reaction Emil Abderhalden * Abney effect, Abney s law of additivity William de… … Wikipedia
Rijke tube — Rijke s tube turns heat into sound, by creating a self amplifying standing wave. It is an entertaining phenomenon in acoustics and is an excellent example of resonance. [ thumb|right|A simple construction of the Rijke tube, with a wire mesh in… … Wikipedia
Two-photon absorption — (TPA) is the simultaneous absorption of two photons of identical or different frequencies in order to excite a molecule from one state (usually the ground state) to a higher energy electronic state. The energy difference between the involved… … Wikipedia
