Idler
51reverse idler gear — A gear used in the transmission to produce a reverse rotation of the transmission output shaft …
52AAR wheel arrangement — The AAR wheel arrangement system is a method of classifying locomotive (or unit) wheel arrangements that was developed by the Association of American Railroads. It is essentially a simplification of the European UIC classification, and it is… …
53Delayed choice quantum eraser — Quantum mechanics Uncertainty principle …
54Optical parametric oscillator — Infrared optical parametric oscillator An optical parametric oscillator (OPO) is a parametric oscillator which oscillates at optical frequencies. It converts an input laser wave (called pump ) into two output waves of lower frequency (ωs,ωi) by… …
55Phonograph — Turntable redirects here. For other uses, see Turntable (disambiguation). Edison cylinder phonograph ca. 1899 …
56Nonlinear optics — (NLO) is the branch of optics that describes the behaviour of light in nonlinear media, that is, media in which the dielectric polarization P responds nonlinearly to the electric field E of the light. This nonlinearity is typically only observed… …
57Gear ratio — The gear ratio is the relationship between the number of teeth on two gears that are meshed or two sprockets connected with a common roller chain, or the circumferences of two pulleys connected with a drive belt. General description In the… …
58Optical parametric amplifier — An optical parametric amplifier, abbreviated OPA, is a laser light source that emits light of variable wavelengths by an optical parametric amplification process. Contents 1 Optical parametric generation (OPG) 2 Optical parametric amplification… …
59Samuel Johnson — Pour les articles homonymes, voir Johnson. Samuel Johnson …
60Samuel Johnson — For other people named Samuel Johnson, see Samuel Johnson (disambiguation). Samuel Johnson LLD MA Samuel Johnson c. 1772, painted by Sir Joshua Reynolds Born …
