Columbia Encyclopedia

Search results

500 results found

air conditioning

(Encyclopedia)CE5 Cross section of air conditioning unit. air conditioning, mechanical process for controlling the humidity, temperature, cleanliness, and circulation of air in buildings and rooms. Indoor air i...

Bernoulli's principle

(Encyclopedia)CE5 Bernoulli's principle Bernoulli's principle, physical principle formulated by Daniel Bernoulli that states that as the speed of a moving fluid (liquid or gas) increases, the pressure within th...

octane number

(Encyclopedia)octane number, figure of merit representing the resistance of gasoline to premature detonation when exposed to heat and pressure in the combustion chamber of an internal-combustion engine. Such detona...

stellar evolution

(Encyclopedia)CE5 The above Hertzsprung-Russell (H-R) diagram shows the track of stellar evolution for a typical star. After spending much of its life evolving toward or along the main sequence, the star becomes...

sound

(Encyclopedia)CE5 Sound waves: An air pressure wave radiating outward from a loudspeaker is perceived as sound. sound, any disturbance that travels through an elastic medium such as air, ground, or water to be ...

manometer

(Encyclopedia)manometer mənŏmˈĭtər [key]: see pressure. ...

conduction

(Encyclopedia)conduction, transfer of heat or electricity through a substance, resulting from a difference in temperature between different parts of the substance, in the case of heat, or from a difference in elect...

Manchester terrier

(Encyclopedia)Manchester terrier, breed of sleek, alert terrier developed in England in the 19th cent. There are two varieties, the standard and the toy (see toy dog). The standard variety stands from 14 to 16 in. ...

calorimetry

(Encyclopedia)calorimetry kălˌərĭmˈətrē [key], measurement of heat and the determination of heat capacity. Heat is evolved in exothermic processes and absorbed in endothermic processes; such processes includ...

chemical reaction

(Encyclopedia)chemical reaction, process by which one or more substances may be transformed into one or more new substances. Energy is released or is absorbed, but no loss in total molecular weight occurs. When, fo...