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aerodynamics

(Encyclopedia)aerodynamics, study of gases in motion. As the principal application of aerodynamics is the design of aircraft, air is the gas with which the science is most concerned. Although aerodynamics is primar...

helicopter

(Encyclopedia)helicopter, type of aircraft in which lift is obtained by means of one or more power-driven horizontal propellers called rotors. When the rotor of a helicopter turns it produces reaction torque which ...

Lorentz contraction

(Encyclopedia)Lorentz contraction lôrˈĕnts [key], in physics, contraction or foreshortening of a moving body in the direction of its motion, proposed by H. A. Lorentz on theoretical grounds and based on an earli...

oxycodone

(Encyclopedia) oxycodone is a synthetic opioid developed to treat pain. Oxycodone was originally developed in Germany in 1917 from a synthesis of thebaine, an alkaloi...

marine engine

(Encyclopedia)marine engine, machine for the propulsion of watercraft. The earliest marine power plants, reciprocating steam engines, were used almost exclusively until the early 1900s. In later ship construction t...

planarian

(Encyclopedia)planarian, common name for several genera of the free-living (turbellarian) flatworms belonging to the order Tricladida, a name that derives from their characteristic three-branched digestive cavities...

Teller, Edward

(Encyclopedia)Teller, Edward, 1908–2003, American physicist, b. Budapest, Hungary, Ph.D. Univ. of Leipzig, 1930, where he studied under Werner Heisenberg. Fleeing the Nazis, he came to the United States in 1935 a...

Stevens

(Encyclopedia)Stevens, family of U.S. inventors. John Stevens, 1749–1838, b. New York City, was graduated from King's College (now Columbia Univ.) in 1768. He studied law (1768–71) and soon joined his father, a...

Wisconsin, state, United States

(Encyclopedia)CE5 Wisconsin wĭskŏnˈsən, –sĭn [key], upper midwestern state of the United States. It is bounded by Lake Superior and the Upper Peninsula of Michigan, from which it is divided in part by the...

diving, springboard and platform

(Encyclopedia)diving, springboard and platform, sport of entering the water from a raised position, often while executing tumbles, twists, and other acrobatic maneuvers. In most dives the upper part of the body ent...