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circuit breaker

(Encyclopedia)circuit breaker, electric device that, like a fuse, interrupts an electric current in a circuit when the current becomes too high. The advantage of a circuit breaker is that it can be reset after it h...

Rural Electrification Administration

(Encyclopedia)Rural Electrification Administration (REA), former agency of the U.S. Dept. of Agriculture charged with administering loan programs for electrification and telephone service in rural areas. The REA wa...

Fleming, Sir John Ambrose

(Encyclopedia)Fleming, Sir John Ambrose, 1849–1945, English electrical engineer. He was a leader in the development of electric lighting, the telephone, and wireless telegraphy in England and the inventor of a th...

Gramme, Zénobe-Théophile

(Encyclopedia)Gramme, Zénobe-Théophile zānôbˈ tāôfēlˈ gräm [key], 1826–1901, Belgian electrical engineer. While working as a model maker for a Parisian manufacturer of electrical devices, Gramme became ...

hearing aid

(Encyclopedia)hearing aid, device used in some forms of deafness to amplify sound before it reaches the auditory organs. Modern hearing aids are electronic. They contain a tiny receiver and a transistor amplifier, ...

commutator

(Encyclopedia)commutator, device used in an electric generator to convert the alternating current produced in the generator into direct current before the current is sent into an external circuit; it is basically a...

thyristor

(Encyclopedia)thyristor, semiconductor switch used chiefly in power-control applications. Also called a silicon-controlled rectifier (SCR; see rectifier), it is a variation of the transistor. A thyristor is capable...

watt

(Encyclopedia)watt [for James Watt], abbr. W, unit of power, or work done per unit time, equal to 1 joule per second. It is used as a measure of electrical and mechanical power. One watt is the amount of power that...

governor, device

(Encyclopedia)governor, automatic device used to regulate and control such variables as speed or pressure in the functioning of an engine or other machine. A governor may be an electric, hydraulic, or mechanical de...

mass spectrograph

(Encyclopedia)mass spectrograph, device used to separate electrically charged particles according to their masses; a form of the instrument known as a mass spectrometer is often used to measure the masses of isotop...