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Torvalds, Linus Benedict

(Encyclopedia)Torvalds, Linus Benedict, 1969–, Finnish-American computer software engineer. A member of Finland's Swedish-speaking minority, he attended the Univ. of Helsinki (M.S., 1996), where he also taught. I...

center of mass

(Encyclopedia)center of mass, the point at which all the mass of a body may be considered to be concentrated in analyzing its motion. The center of mass of a sphere of uniform density coincides with the center of t...

pound

(Encyclopedia)pound, abbr. lb, unit of either mass or force in the customary system of English units of measurement. Two different pounds of mass are defined, one in the avoirdupois system of units and one in the T...

thermodynamics

(Encyclopedia)thermodynamics, branch of science concerned with the nature of heat and its conversion to mechanical, electric, and chemical energy. Historically, it grew out of efforts to construct more efficient he...

gram

(Encyclopedia)gram, abbr. g, unit of mass equal to 0.001 kilogram, the basic unit of mass in the metric system. The gram is the unit of mass in the cgs system. It is approximately equal to 0.035 avoirdupois ounce, ...

Brahmagupta

(Encyclopedia)Brahmagupta bräˌməgo͝opˈtə [key], c.598–c.660, Indian mathematician and astronomer. He was among the first to meaningfully discuss the concepts of zero and of negative numbers. He wrote in ver...

Byrom, John

(Encyclopedia)Byrom, John bīˈrəm [key], 1692–1763, English shorthand expert and poet, educated at Trinity College, Cambridge. He devised an early shorthand system, which he taught in Manchester. Although he co...

watershed

(Encyclopedia)watershed, elevation or divide separating the catchment area, or drainage basin, of one river system or group of river systems from another system or group of systems. The term is also often used syno...

Beer, George Louis

(Encyclopedia)Beer, George Louis, 1872–1920, American historian, b. Staten Island, N.Y. He was a tobacco importer for 10 years but also lectured on European history at Columbia from 1893 to 1897. After 1903 he de...

X-ray astronomy

(Encyclopedia)X-ray astronomy, study of celestial objects by means of the X rays they emit, in the wavelength range from 0.01 to 10 nanometers. X-ray astronomy dates to 1949 with the discovery that the sun emits X ...
 

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