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mass, in physics

(Encyclopedia)mass, in physics, the quantity of matter in a body regardless of its volume or of any forces acting on it. The term should not be confused with weight, which is the measure of the force of gravity (se...

hemophilia

(Encyclopedia)hemophilia hēˌməfĭlˈēə, –fēlˈyə [key], genetic disease in which the clotting ability of the blood is impaired and excessive bleeding results. The disease is transmitted through females but...

cystic fibrosis

(Encyclopedia)cystic fibrosis sĭsˈtĭk fībrōˈsĭs [key], inherited disorder of the exocrine glands (see gland), affecting children and young people; median survival is 25 years in females and 30 years in males...

fireproofing

(Encyclopedia)fireproofing, method of making normally combustible materials as nearly noncombustible as possible. Fireproofing generally applies to textiles and construction materials that are treated with a soluti...

smoke

(Encyclopedia)smoke, visible gaseous product of incomplete combustion. Smoke varies with its source, but it usually comprises hot gas and suspended particles of carbon and tarry substances, or soot. To reduce the a...

pearl, gem

(Encyclopedia)pearl, hard, rounded secretion formed inside the shell of certain mollusks, used as a gem. It is secreted by the epithelial cells of the mantle, a curtain of tissue between the shell and body mass, an...

work

(Encyclopedia)work, in physics and mechanics, transfer of energy by a force acting to displace a body. Work is equal to the product of the force and the distance through which it produces movement. Although both fo...

steam engine

(Encyclopedia)CE5 Steam engine steam engine, machine for converting heat energy into mechanical energy using steam as a medium, or working fluid. When water is converted into steam it expands, its volume increa...

moon

(Encyclopedia)CE5 The moon: Near side CE5 The moon: Far side moon, natural satellite of a planet (see satellite, natural) or dwarf planet, in particular, the single natural satellite of the earth. It is no...

lithium

(Encyclopedia)lithium lĭthˈēəm [key] [Gr.,=stone], metallic chemical element; symbol Li; at. no. 3; interval in which at. wt. ranges 6.938–6.997; m.p. about 180.54℃; b.p. about 1,342℃; sp. gr. .534 at 20�...