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generator

(Encyclopedia)CE5 Generator: The rotation of the conducting coil of wire in a magnetic field causes a current to be induced in the coil. This current is alternating and is conducted from the coil by means of sli...

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...

Plücker, Julius

(Encyclopedia)Plücker, Julius yo͞oˈlyo͝os plüˈkər [key], 1801–68, German mathematician and physicist. He became professor of mathematics (1836) and of physics (1847) at the Univ. of Bonn. He is known for h...

Van Vleck, John Hasbrouck

(Encyclopedia)Van Vleck, John Hasbrouck, 1899–1980, American physicist, b. Middletown, Conn., Ph.D. Harvard, 1922. As a professor at Harvard, Van Vleck developed fundamental theories on the quantum mechanics of m...

electrodynamics

(Encyclopedia)electrodynamics, study of phenomena associated with charged bodies in motion and varying electric and magnetic fields (see charge; electricity); since a moving charge produces a magnetic field, electr...

geophysics

(Encyclopedia)geophysics, study of the structure, composition, and dynamic changes of the earth, its atmosphere, hydrosphere and magnetosphere, based on the principles of physics. The term was probably first used i...

transformer

(Encyclopedia)transformer, electrical device used to transfer an alternating current or voltage from one electric circuit to another by means of electromagnetic induction. The simplest type of transformer consists ...

Schawlow, Arthur Leonard

(Encyclopedia)Schawlow, Arthur Leonard shôˈlō [key], 1921–99, American physicist, b. Mount Vernon, N.Y., grad. Univ. of Toronto (Ph.D. 1949). Although his research focused on optics, in particular, lasers and ...

Europa, in astronomy

(Encyclopedia)Europa yo͝orōˈpə [key], in astronomy, one of the 39 known moons, or natural satellites, of Jupiter. Magnetic-field data collected by the space probe Galileo in 2002 strongly indicated a liquid-wat...

Kursk

(Encyclopedia)Kursk ko͝orsk [key], city (1989 pop. 424,000), capital of Kursk region, W European Russia, at the confluence of the Tuskor and Seim rivers. An important rail junction, it has machine, chemical, and s...