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shock wave

(Encyclopedia)shock wave, wave formed of a zone of extremely high pressure within a fluid, especially the atmosphere, that propagates through the fluid at a speed in excess of the speed of sound. A shock wave is ca...

daylight saving time

(Encyclopedia)daylight saving time (DST), time observed when clocks and other timepieces are set ahead so that the sun will rise and set later in the day as measured by civil time. The amount of daylight on a given...

gluon

(Encyclopedia)gluon, an elementary particle that mediates, or carries, the strong, or nuclear, force. In quantum chromodynamics (QCD), the quantum field theory of strong interactions, the interaction of quarks (to ...

flame

(Encyclopedia)flame, phenomenon associated with the chemical reaction of a gas that has been heated above its kindling temperature with some other gas, usually atmospheric oxygen (see combustion). The heat and ligh...

magnetic levitation

(Encyclopedia)magnetic levitation or maglev măgˈlĕv [key], support and often propulsion of objects or vehicles by the use of magnets. The magnets used in magnetic levitation suspend an object free of contact wit...

amplitude

(Encyclopedia)amplitude ămˈplĭto͞odˌ [key], in physics, maximum displacement from a zero value or rest position. In the harmonic motion of a pendulum, the amplitude of the swing is the greatest distance reache...

carbon

(Encyclopedia)CE5 The three solid forms of pure carbon: In the diamond crystal each carbon atom is surrounded symmetrically by four other carbons (at each of the four corners of a tetrahedron). In the graphite c...

MacCready, Paul Beattie

(Encyclopedia)MacCready, Paul Beattie, 1925–2007, American engineer and inventor known for his achievements in human-powered flight, b. New Haven, Conn., Ph.D. California Institute of Technology, 1952. In 1997 he...

Massachusetts Institute of Technology

(Encyclopedia)Massachusetts Institute of Technology, at Cambridge; coeducational; chartered 1861, opened 1865 in Boston, moved 1916. It has long been recognized as an outstanding technological institute and its Slo...

Crookes, Sir William

(Encyclopedia)Crookes, Sir William, 1832–1919, English chemist and physicist. After serving at the Radcliffe Observatory, Oxford, and teaching chemistry at Chester Training College, he retired to work in his own ...