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sound recording

(Encyclopedia)sound recording, process of converting the acoustic energy of sound into some form in which it can be permanently stored and reproduced at any time. In 1855 the inventor Leon Scott constructed a devic...

streptococcus

(Encyclopedia)streptococcus strĕpˌtəkŏkˈəs [key], any of a group of gram-positive bacteria, genus Streptococcus, some of which cause disease. Streptococci are spherical and divide by fission, but they remain ...

light

(Encyclopedia)light, visible electromagnetic radiation. Of the entire electromagnetic spectrum, the human eye is sensitive to only a tiny part, the part that is called light. The wavelengths of visible light range ...

mathematics

(Encyclopedia)mathematics, deductive study of numbers, geometry, and various abstract constructs, or structures; the latter often “abstract” the features common to several models derived from the empirical, or ...

meteorology

(Encyclopedia)meteorology, branch of science that deals with the atmosphere of a planet, particularly that of the earth, the most important application of which is the analysis and prediction of weather. Individual...

motion

(Encyclopedia)motion, the change of position of one body with respect to another. The rate of change is the speed of the body. If the direction of motion is also given, then the velocity of the body is determined; ...

opium

(Encyclopedia)opium, substance derived by collecting and drying the milky juice in the unripe seed pods of the opium poppy, Papaver somniferum. Opium varies in color from yellow to dark brown and has a characterist...

wave, in physics

(Encyclopedia)wave, in physics, the transfer of energy by the regular vibration, or oscillatory motion, either of some material medium or by the variation in magnitude of the field vectors of an electromagnetic fie...

satellite, artificial

(Encyclopedia)CE5 A. Nimbus weather satellite B. Syncom communications satellite satellite, artificial, object constructed by humans and placed in orbit around the earth or other celestial body (see also space ...

logic

(Encyclopedia)logic, the systematic study of valid inference. A distinction is drawn between logical validity and truth. Validity merely refers to formal properties of the process of inference. Thus, a conclusion w...