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gauss

(Encyclopedia)gauss gous [key] [for C. F. Gauss], abbr. G, unit of magnetic flux density (see flux, magnetic) equal to 0.0001 (10−4) weber per square meter. Since this unit is derived from the cgs system of units...

pyrrhotite

(Encyclopedia)pyrrhotite pĭrˈətīt [key] or magnetic pyrites, bronze-yellow to bronze-red mineral, a sulfide of iron sometimes containing nickel. It tarnishes easily and is somewhat magnetic. It crystallizes in ...

tape recorder

(Encyclopedia)CE5 Magnetic tape-recording system tape recorder, device for recording and replaying of sound, video, and digital information on plastic (usually polyester) or paper tape. The tape is coated with ...

Oersted, Hans Christian

(Encyclopedia)Oersted or Ørsted, Hans Christian häns krĭsˈtyän örˈstĭᵺ [key], 1777–1851, Danish physicist and chemist. He was professor at Copenhagen from 1806. His discovery (1819) that a magnetic need...

magnetite

(Encyclopedia)magnetite măgˈnətīt [key], lustrous black, magnetic mineral, Fe3O4. It occurs in crystals of the cubic system, in masses, and as a loose sand. It is one of the important ores of iron (magnetic iro...

pole, in electricity and magnetism

(Encyclopedia)pole, in electricity and magnetism, point where electric or magnetic force appears to be concentrated. A single electric charge located at a point is sometimes referred to as an electric monopole. An ...

Rayleigh, John William Strutt, 3d Baron

(Encyclopedia)Rayleigh, John William Strutt, 3d Baron rāˈlē [key], 1842–1919, English physicist. He was professor at Cambridge (1879–84) and at the Royal Institution (1887–1905), and chancellor of Cambridg...

motor, electric

(Encyclopedia)CE5 Motor: In the AC motor, current fed to the conducting loop of wire causes it to rotate in the magnetic field, thus turning the shaft on which the loop is mounted. In the DC motor, the direction...

psychological test

(Encyclopedia)psychological test, any of a variety of testing procedures for measuring psychological traits and behavior, or for studying some specialized aspect of ability. Several forms of testing have arisen fro...

Gilbert, William

(Encyclopedia)Gilbert, William, 1544–1603, English scientist and physician. He studied medicine at Cambridge (M.D., 1569), where he was elected a Fellow of St. John's College, and set up practice in London, becom...