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fusion

(Encyclopedia)fusion, in physics. 1 The change of a substance from the solid to the liquid state, also known as melting. The heat given up by a unit mass of a substance during fusion is called the latent heat of fu...

temperature

(Encyclopedia)CE5 Temperature scales temperature, measure of the relative warmth or coolness of an object. Temperature is measured by means of a thermometer or other instrument having a scale calibrated in unit...

streetcar

(Encyclopedia)streetcar, small, self-propelled railroad car, similar to the type used in rapid-transit systems, that operates on tracks running through city streets and is used to carry passengers. Most often cars ...

personal watercraft

(Encyclopedia)personal watercraft (PWC), a lightweight vessel usually less than 16 ft (5 m) long that uses an inboard water jet pump, powered by an internal-combustion engine, as its primary source of propulsion. T...

compound

(Encyclopedia)compound, in chemistry, a substance composed of atoms of two or more elements in chemical combination, occurring in a fixed, definite proportion and arranged in a fixed, definite structure. A compound...

chemistry

(Encyclopedia)chemistry, branch of science concerned with the properties, composition, and structure of substances and the changes they undergo when they combine or react under specified conditions. Organic chemi...

rectifier

(Encyclopedia)rectifier, component of an electric circuit used to change alternating current to direct current. Rectifiers are made in various forms, all operating on the principle that current passes through them ...

hydrotherapy

(Encyclopedia)hydrotherapy, use of water in the treatment of illness or injury. Although the medicinal and hygienic value of water was recognized by the early Greeks, hydrotherapy attained its widest use in the 18t...

heatstroke

(Encyclopedia)heatstroke, profound disturbance of the heat-regulating mechanism of the body, also known as sunstroke. It is characterized by extremely high body temperatures and sometimes by convulsions and coma. T...

neutralization

(Encyclopedia)neutralization, chemical reaction, according to the Arrhenius theory of acids and bases, in which a water solution of acid is mixed with a water solution of base to form a salt and water; this reactio...