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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...

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...

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 ...

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 ...

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...

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...

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...