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heat

(Encyclopedia)heat, nonmechanical energy in transit, associated with differences in temperature between a system and its surroundings or between parts of the same system. The study of heat and its relationship ...

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...

heat exhaustion

(Encyclopedia)heat exhaustion, condition caused by overexposure to sunlight or another heat source and resulting in dehydration and salt depletion, also known as heat prostration. The symptoms are severe headaches,...

heat prostration

(Encyclopedia)heat prostration: see heat exhaustion; heatstroke. ...

heat pump

(Encyclopedia)heat pump: see air conditioning. ...

latent heat

(Encyclopedia)latent heat, heat change associated with a change of state or phase (see states of matter). Latent heat, also called heat of transformation, is the heat given up or absorbed by a unit mass of a substa...

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...

prickly heat

(Encyclopedia)prickly heat (miliaria), inflammatory skin eruption due to obstruction of the sweat glands by keratin, the substance that forms the horny cells of the epidermis. It consists of blisterlike elevations ...

heat of combustion

(Encyclopedia)heat of combustion, heat released during combustion. In particular, it is the amount of heat released when a given amount (usually 1 mole) of a combustible pure substance is burned to form incombustib...

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...