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microprocessor

(Encyclopedia)microprocessor, integrated circuit containing the arithmetic, logic, and control circuitry required to interpret and execute instructions from a computer program. When combined with other integrated c...

lock, canal

(Encyclopedia)lock, canal, stretch of water enclosed by gates, one at each end, built into a canal or river for the purpose of raising or lowering a vessel from one water level to another. A lock may also be built ...

magnetron

(Encyclopedia)magnetron măgˈnĭtrŏnˌ [key], vacuum tube oscillator (see electron tube) that generates high-power electromagnetic signals in the microwave frequency range. Its operation is based on the combined ...

Hancock, Herbie

(Encyclopedia) Hancock, Herbie (Herbert Jeffrey Hancock), 1940- , American jazz pianist, composer, and bandleader, b. Chicago, Il., Grinnell College (B.S.E., 1960, H...

torque

(Encyclopedia)torque, in physics, that which tends to change the rate of rotation of a body; also called the moment of force. The torque produced by rotating parts of an electric motor or internal-combustion engine...

resistance, in electricity

(Encyclopedia)resistance, property of an electric conductor by which it opposes a flow of electricity and dissipates electrical energy away from the circuit, usually as heat. Optimum resistance is provided by a con...

Bjerknes, Vilhelm Frimann Koren

(Encyclopedia)Bjerknes, Vilhelm Frimann Koren vĭlˈhĕlm frēˈmän kôˈrən byĕrkˈnĕs [key], 1862–1951, Norwegian physicist and pioneer in modern meteorology. He worked on applying hydrodynamic and thermody...

clock

(Encyclopedia)CE5 A pendulum clock: Weight-driven clock mechanism clock, instrument for measuring and indicating time. Predecessors of the clock were the sundial, the hourglass, and the clepsydra. See also watc...

semiconductor

(Encyclopedia)CE5 N-type and P-type crystals: In a pure silicon crystal each silicon atom (Si) is surrounded by four valence electrons. In the N-doped semiconductor, illustrated in the left-hand figure, some sil...

Gauss, Carl Friedrich

(Encyclopedia)Gauss, Carl Friedrich kärl frēˈdrĭkh gous [key], born Johann Friederich Carl Gauss, 1777–1855, German mathematician, physicist, and astronomer. Gauss was educated at the Caroline College, Brunsw...