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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...

airplane

(Encyclopedia)CE5 A. Side view of jet-propelled airplane B. Top view airplane, aeroplane, or aircraft, heavier-than-air vehicle, mechanically driven and fitted with fixed wings that support it in flight thro...

ship

(Encyclopedia)ship, large craft in which persons and goods may be conveyed on water. In the U.S. Navy the term boat refers to any vessel that is small enough to be hoisted aboard a ship, and ship is used for any la...

airship

(Encyclopedia)airship, an aircraft that consists of a cigar-shaped gas bag, or envelope, filled with a lighter-than-air gas to provide lift, a propulsion system, a steering mechanism, and a gondola accommodating pa...

printing

(Encyclopedia)printing, means of producing reproductions of written material or images in multiple copies. There are four traditional types of printing: relief printing (with which this article is mainly concerned)...

entropy

(Encyclopedia)entropy ĕnˈtrəpē [key], quantity specifying the amount of disorder or randomness in a system bearing energy or information. Originally defined in thermodynamics in terms of heat and temperature, e...

propeller

(Encyclopedia)propeller, device consisting of a hub with one or more blades that propels a craft to which it is attached by rotating its blades in a fluid such as air or water. In the latter part of the 1830s the S...

radiator

(Encyclopedia)radiator, device used to heat an area surrounding it or to cool a fluid circulating within it. The familiar radiators of steam and hot water heating systems in buildings are misnamed, as they operate ...

magnesium

(Encyclopedia)magnesium măgnēˈzēəm, –zhəm [key], metallic chemical element; symbol Mg; at. no. 12; at. wt. 24.3050; m.p. about 648.8℃; b.p. about 1,090℃; sp. gr. 1.738 at 20℃; valence +2. In 1808, Sir...

screw

(Encyclopedia)screw, simple machine consisting essentially of a solid cylinder, usually of metal, around which an inclined plane winds spirally, either clockwise or counterclockwise. It is used to fasten one object...