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lighting

(Encyclopedia)CE5 Incandescent lamp CE5 Basic fluorescent lamp lighting, light produced by artificial means to allow visibility in enclosures and at night. For stage lighting, see scene design and stage ligh...

radioactivity

(Encyclopedia)CE5 Effects of a magnetic field on the products of radioactivity CE5 Disintegration series: Radioactive decay of radium-226 into lead-206 radioactivity, spontaneous disintegration or decay of t...

radio astronomy

(Encyclopedia)radio astronomy, study of celestial bodies by means of the electromagnetic radio frequency waves they emit and absorb naturally. Radio waves also come from outside the Milky Way. These extragalact...

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...

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...

chain

(Encyclopedia)chain, flexible series of connected links used in various ways, especially for the transmission of motive power, for hoisting (see pulley), and for securing or fastening. Commonly, mechanical energy f...

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...

hummingbird

(Encyclopedia)hummingbird, common name for members of the family Trochilidae, small, strictly New World birds, related to the swifts, and found chiefly in the mountains of South America. Hummingbirds vary in size f...

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....

Five-Year Plan

(Encyclopedia)Five-Year Plan, Soviet economic practice of planning to augment agricultural and industrial output by designated quotas for a limited period of usually five years. Nations other than the former USSR a...