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inclined plane

(Encyclopedia)CE5 Inclined plane inclined plane, simple machine, consisting of a sloping surface, whose purpose is to reduce the force that must be applied to raise a load. To raise a body vertically a force mu...

dream

(Encyclopedia)dream, mental activity associated with the rapid-eye-movement (REM) period of sleep. It is commonly made up of a number of visual images, scenes or thoughts expressed in terms of seeing rather than in...

Dyson, Freeman John

(Encyclopedia)Dyson, Freeman John dīˈsən [key], 1923–2020, British-American theoretical physicist and mathematician, studied Trinity College, Cambridge (B.A., 1945) and Cornell. He did bomber operations resear...

guanine

(Encyclopedia)guanine gwäˈnēn [key], organic base of the purine family. It was reported (1846) to be in the guano of birds; later (1879–84) it was established as one of the major constituents of nucleic acids....

kinetic-molecular theory of gases

(Encyclopedia)kinetic-molecular theory of gases, physical theory that explains the behavior of gases on the basis of the following assumptions: (1) Any gas is composed of a very large number of very tiny particles ...

solid

(Encyclopedia)solid, one of the three commonly recognized states in which matter occurs, i.e., that state, as distinguished from liquid and gas, in which a substance has both a definite shape and a definite volume....

Pennebaker, D. A.

(Encyclopedia)Pennebaker, D. A. (Donn Alan Pennebaker), 1925–2019, pioneering documentary filmmaker, b. Evanston, Ill. His first film, Daybreak Express (1958), is a five-minute short detailing New York's doomed T...

phosphate

(Encyclopedia)phosphate, salt or ester of phosphoric acid, H3PO4. Because phosphoric acid is tribasic (having three replaceable hydrogen atoms), it forms monophosphate, diphosphate, and triphosphate salts in which ...

water mold

(Encyclopedia)water mold, common name for a group of multinucleated organisms that superficially resemble fungi but are now recognized as having an independent evolutionary lineage and are placed in the kingdom Pro...

Benn, Anthony Wedgwood

(Encyclopedia)Benn, Anthony Wedgwood (Tony Benn), 1925–2014, British politician, b. London, grad. New College, Oxford. After working for the British Broadcasting Corporation (1949–50), he was elected a Labour m...