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Fujita scale

(Encyclopedia)Fujita scale fo͞ojēˈtə, fo͞oˈjētə [key] or F-Scale, scale for rating the severity of tornadoes as a measure of the damage they cause, devised in 1951 by the Japanese-American meteorologist Tet...

Richter scale

(Encyclopedia)Richter scale rĭkˈtər [key], measure of the magnitude of seismic waves from an earthquake. Devised in 1935 by the American seismologist Charles F. Richter (1900–1985) and technically known as the...

degree-day

(Encyclopedia)degree-day, a unit of measure used to estimate the fuel and power requirements in heating and cooling a building; it is equal to a difference of 1 degree between the outdoor daily average temperature ...

grease

(Encyclopedia)grease, mixture of lubricant and thickener. It is used to reduce friction between surfaces from which oils would leak away or cause damage by dripping, or where lubrication must be assured for extende...

hysteresis

(Encyclopedia)hysteresis hĭsˌtərēˈsĭs [key], phenomenon in which the response of a physical system to an external influence depends not only on the present magnitude of that influence but also on the previous...

psychrometer

(Encyclopedia)psychrometer sīkrŏmˈĭtər [key], one of many instruments used for measuring the water vapor content or relative humidity of the atmosphere. It consists of two identical thermometers—the wet-bulb...

humidity

(Encyclopedia)humidity, moisture content of the atmosphere, a primary element of climate. Humidity measurements include absolute humidity, the mass of water vapor per unit volume of natural air; relative humidity (...

vaporization

(Encyclopedia)vaporization, change of a liquid or solid substance to a gas or vapor. There is fundamentally no difference between the terms gas and vapor, but gas is used commonly to describe a substance that appea...
 

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