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Moseley, Henry Gwyn Jeffreys

(Encyclopedia)Moseley, Henry Gwyn Jeffreys mōzˈlē [key], 1887–1915, English physicist, grad. Trinity College, Oxford, 1910. He began his research under Ernest Rutherford while serving as lecturer at the Univ. ...

binary star

(Encyclopedia)CE5 A. Eclipsing binary: Primary component passing behind secondary (dimmer) component B. Light curve for eclipsing binary binary star or binary system, pair of stars that are held together by the...

physical fitness

(Encyclopedia)physical fitness, combined good health and physical development. The object of any program of physical fitness is to maximize an individual's health, strength, endurance, and skill relative to age, se...

alternating current

(Encyclopedia)alternating current, abbr. AC, a flow of electric charge that undergoes periodic reverses in direction. In North America ordinary household current alternates at a frequency of 60 times per second. Se...

genealogy

(Encyclopedia)genealogy jēˌnēŏlˈəjē, –ălˈ–, jĕ– [key], the study of family lineage. Genealogies have existed since ancient times. Family lineage was originally transmitted through oral tradition and...

Marsilius of Padua

(Encyclopedia)Marsilius of Padua märsĭlˈēəs, păˈdyo͞oə [key], d. c.1342, Italian political philosopher. He is satirically called Marsiglio. Little is known with certainty of his life except that he was rec...

Concert of Europe

(Encyclopedia)Concert of Europe, term used in the 19th cent. to designate a loose agreement by the major European powers to act together on European questions of common interest. The concert emerged after the Congr...

tartar, dental

(Encyclopedia)tartar, dental, precipitate of saliva that accumulates around teeth at the gum line. Composed primarily of calcium salts, tartar forms as a hard brownish substance that irritates gums and causes them ...

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