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British thermal unit

(Encyclopedia)British thermal unit, abbr. Btu, unit for measuring heat quantity in the customary system of English units of measurement, equal to the amount of heat required to raise the temperature of one pound of...

thermal unit

(Encyclopedia)thermal unit: see British thermal unit. ...

Btu

(Encyclopedia)Btu: see British thermal unit.

thermal capacity

(Encyclopedia)thermal capacity: see heat capacity. ...

thermal pollution

(Encyclopedia)thermal pollution: see water pollution. ...

astronomical unit

(Encyclopedia)astronomical unit (AU), mean distance between the earth and sun; one AU is c.92,960,000 mi (149,604,970 km). The astronomical unit is the principal unit of measurement within the solar system, e.g., M...

specific heat

(Encyclopedia)specific heat, ratio of the heat capacity of a substance to the heat capacity of a reference substance, usually water. Heat capacity is the amount of heat needed to change the temperature of a unit ma...

European Currency Unit

(Encyclopedia)European Currency Unit: see European Monetary System. ...

atomic mass unit

(Encyclopedia)atomic mass unit or amu, in chemistry and physics, unit defined as exactly 1⁄12 the mass of an atom of carbon-12, the isotope of carbon with six protons and six neutrons in its nucleus. One amu is e...

heat capacity

(Encyclopedia)heat capacity or thermal capacity, ratio of the change in heat energy of a unit mass of a substance to the change in temperature of the substance; like its melting point or boiling point, the heat cap...