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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...

tempo

(Encyclopedia)tempo [Ital.,=time], in music, the speed of a composition. The composer's intentions as to tempo are conventionally indicated by a set of Italian terms, of which the principal ones are presto (very fa...

Trent, Council of

(Encyclopedia)Trent, Council of, 1545–47, 1551–52, 1562–63, 19th ecumenical council of the Roman Catholic Church, convoked to meet the crisis of the Protestant Reformation. Earlier efforts at reforming the ch...

lubrication

(Encyclopedia)lubrication, introduction of a substance between the contact surfaces of moving parts to reduce friction and to dissipate heat. A lubricant may be oil, grease, graphite, or any substance—gas, liquid...

elevator, in machinery

(Encyclopedia)elevator, in machinery, device for transporting people or goods from one level to another. The term is applied to the enclosed structures as well as the open platforms used to provide vertical transpo...

ergonomics

(Encyclopedia)ergonomics, the engineering science concerned with the physical and psychological relationship between machines and the people who use them. The ergonomicist takes an empirical approach to the study o...

camera

(Encyclopedia)CE5 Image formed by a camera camera, lightproof box or container, usually fitted with a lens, which gathers incoming light and concentrates it so that it can be directed toward the film (in an opt...

museums of science

(Encyclopedia)museums of science, institutions or buildings where collections relevant to science and technology are preserved and displayed to promote education and research. While the preponderance of these museu...

Maccabees, books of the Bible

(Encyclopedia)Maccabees, two books included in the Septuagint and placed as the last two books in the Old Testament of the Vulgate; they are not included in the Hebrew Bible and are placed in the Apocrypha in Prote...

Moss, Sir Stirling Craufurd

(Encyclopedia)Moss, Sir Stirling Craufurd, 1929–2020, British auto racing driver. Known for his sportsmanship, speed, and courage, Moss became a full-time driver on the Grand Prix circuit in 1953. He subsequently...