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electromagnet ... Elgin

electromagnet: device consisting of a core of magnetic material surrounded by a coil through which an electric current is passed to magnetize the core. An electromagnet is used wherever controllable magnets ...
electromagnetic field: a property of space caused by the motion of an electric charge. A stationary charge will produce only an electric field in the surrounding space. If the charge is moving, ...
electromagnetic radiation: in terms of classical theory, the flow of energy at the universal speed of light through free space or through a material medium in the form of the electric and ...
electromagnetism: science of charge and of the forces and fields associated with charge. Electricity and magnetism are two aspects of electromagnetism.
electromechanical transducer: any type of device that either converts an electrical signal into sound waves (as in a loudspeaker) or converts a sound wave into an electrical signal (as in the microphone). ...
electrometer: instrument designed to measure very small voltages and currents. The quadrant, Lindermann, Hoffman, and Wulf electrometers measure electrical potential between charged elements (e.g., plates or fine quartz fibres) within the ...
electromotive force: energy per unit electric charge that is imparted by an energy source, such as an electric generator or a battery. Energy is converted from one form to another in the ...
electromotive series: listing of chemical species (atoms, molecules, and ions) in the order of their tendency to gain or lose electrons (be reduced or oxidized, respectively), expressed in volts and measured with ...
electromyography: the process of graphically recording the electrical activity of muscle. Normal muscle is electrically silent when at rest, but when it is active, as during contraction or stimulation, an electrical ...
electron: lightest stable subatomic particle known. It carries a negative charge, which is considered the basic unit of electric charge. The rest mass of the electron is 9.109 × 10⁻³¹ kg, ...
electron affinity: in chemistry, the amount of energy liberated when an electron is added to a neutral atom to form a negatively charged ion. The electron affinities of atoms are difficult to ...
electron beam: stream of electrons (as from a betatron) generated by heat (thermionic emission), bombardment of charged atoms or particles (secondary electron emission), or strong electric fields (field emission). Electrons may be ...
electron capture: one of three processes of radioactive disintegration known as beta decay (q.v.).
electron charge: (symbol e), fundamental physical constant expressing the naturally occurring unit of electric charge, equal to 1.6021892 × 10⁻¹⁹ coulomb, or 4.80325 × 10⁻¹⁰ electrostatic unit (esu, or statcoulomb). In addition ...
electron diffraction: bending of a beam of electrons when passing near matter or through spacings in its submicroscopic structure that are comparable in size to the wavelength of an electron. According to ...
electron gun: electrode structure that produces and may control, focus, and deflect a beam of electrons, as in a television picture tube (see ), where the beam produces a visual pattern on ...
electron microscope: microscope that attains extremely high resolution using an electron beam instead of a beam of light to illuminate the object of study. See microscope.
electron optics: branch of physics that is concerned with beams of electrons, their deflection and focusing by electric and magnetic fields, their interference when crossing each other, and their diffraction or bending ...
electron paramagnetic resonance: selective absorption of weak radio-frequency electromagnetic radiation (in the microwave region) by unpaired electrons in the atomic structure of certain materials that simultaneously are subjected to a constant, strong magnetic ...
electron scattering: random collisions of the charge carriers (electrons) with atoms in a crystalline solid (e.g., metal, semiconductor, or insulator) that decreases the mobility of the carriers. The deflection of a beam ...
electron spectroscopy: method of determining the energy with which electrons are bound in chemical species by measuring the kinetic energies of the electrons emitted upon bombardment of the species with X-ray or ...
electron synchrotron: type of synchrotron designed to accelerate electrons to high energies (see synchrotron).
electron tube: device usually consisting of a sealed glass or metal-ceramic enclosure that is used in electronic circuitry to control a flow of electrons. Among the common applications of vacuum tubes are ...
electron volt: unit of energy commonly used in atomic and nuclear physics, equal to the energy gained by an electron (a charged particle carrying unit electronic charge when the electrical potential at ...
electronegativity: in chemistry, the ability of an atom to attract to itself an electron pair shared with another atom in a chemical bond.
electronic carillon: 20th-century musical instrument in which the acoustical tone source-metal tubes, rods, or bars struck by hammers-is picked up electromagnetically or electrostatically and converted into electrical vibrations that are highly amplified ...
electronic configuration: the arrangement of electrons in energy levels around an atomic nucleus. According to the older shell atomic model, electrons occupy several levels from the first shell nearest the nucleus, K, ...
electronic eavesdropping: the act of electronically intercepting conversations without the knowledge or consent of at least one of the participants. Historically, the most common form of electronic eavesdropping has been wiretapping, which ...
electronic game: any interactive game operated by computer circuitry. The machines, or "platforms," on which electronic games are played include general-purpose shared and personal computers, arcade consoles, video consoles connected to home ...
electronic instrument: any musical instrument that produces or modifies sounds by electric, and usually electronic, means. The electronic element in such music is determined by the composer, and the sounds themselves are ...
electronic music: any music involving electronic processing, e.g., recording and editing on tape, and whose reproduction involves the use of loudspeakers.
electronic organ: keyboard musical instrument in which tone is generated by electronic circuits and radiated by loudspeaker. This instrument, which emerged in the early 20th century, was designed as an economical and ...
electronic substrate and package ceramics: advanced industrial materials that, owing to their insulating qualities, are useful in the production of electronic components.
electronic work function: energy (or work) required to withdraw an electron completely from a metal surface. This energy is a measure of how tightly a particular metal holds its electrons-that is, of how ...
electronics: branch of physics and electrical engineering that deals with the emission, behaviour, and effects of electrons and with electronic devices.
electrophile: in chemistry, an atom or a molecule that in chemical reaction seeks an atom or molecule containing an electron pair available for bonding. Electrophilic substances are Lewis acids (compounds that ...
electrophone: any of a class of musical instruments in which the initial sound either is produced by electronic means or is conventionally produced (as by a vibrating string) and electronically amplified. ...
electrophoresis: the movement of electrically charged particles in a fluid under the influence of an electric field. If the liquid rather than the particles is set in motion-e.g., through a fixed ...
electrophotography: any of several image-forming processes, principally xerography and the dielectric process, that rely on photoconductive substances whose electrical resistance decreases when light falls on them; it is the basis of ...
electroplating: process of coating with metal by means of an electric current. Plating metal may be transferred to conductive surfaces (metals) or to nonconductive surfaces (plastics, wood, leather) after the latter ...
electropolishing: electrochemical process of smoothing a metallic surface. The metallic object is made the anode in an electrolytic reaction so controlled that its high spots dissolve, until only a smooth surface ...
electroscope: instrument for detecting the presence of an electric charge or of ionizing radiation, usually consisting of a pair of thin gold leaves suspended from an electrical conductor that leads to ...
electrostatic induction: modification in the distribution of electric charge on one material under the influence of a nearby second object that has an electric charge. Thus, because of the electric force between ...
electrostatic precipitation: method of removing certain impurities (either solid particles or liquid droplets) from air or other gas. It is widely used for removing particles from industrial-waste gases.
electrostriction: property of all electrical nonconductors, or dielectrics, that manifests itself as a relatively slight change of shape, or mechanical deformation, under the application of an electric field. Reversal of the ...
electrotyping: electroforming process for making duplicate plates for relief, or letterpress, printing. The process was first announced in 1838 by M.H. von Jacobi, a German working in St. Petersburg, Russia. Thomas ...
electroweak theory: in physics, the theory that describes both the electromagnetic force and the weak force. Superficially, these forces appear quite different. The weak force acts only across distances smaller than the ...
electrum: natural or artificial alloy of gold with at least 20 percent silver, which was used to make the first known coins in the Western world. Most natural electrum contains copper, ...
elegiac stanza: in poetry, a quatrain in iambic pentameter with alternate lines rhyming. Though the older and more general term for this is heroic stanza, the form became associated specifically with elegiac ...
elegy: meditative lyric poem lamenting the death of a public personage or of a friend or loved one; by extension, any reflective lyric on the broader theme of human mortality. In ...
Elek, Ilona: Hungarian fencer who was the only woman to win two Olympic gold medals in the individual foil competition. In addition to her success in the Olympics, Elek was world champion ...
Elektrostal: city, Moscow oblast (province), western Russia. It lies 36 miles (58 km) east of Moscow city. The name, meaning "electric steel," derives from the high-quality-steel industry established there soon after ...
elementary education: the first stage traditionally found in formal education, beginning at about age 5 to 7 and ending at about age 11 to 13. In the United Kingdom and some other ...
elephant: largest living land animal, characterized by its long trunk (elongated upper lip and nose), columnar legs, and huge head with temporal glands and wide, flat ears. Elephants are grayish to ...
Elephant Man: disfigured man who, after a brief career as a professional "freak," became a patient of London Hospital from 1886 until his death.
elephant seal: either of the two largest pinnipeds (aquatic mammals of the suborder Pinnipedia): the northern elephant seal (species Mirounga angustirostris), now found mainly on coastal islands off California and Baja California; ...
elephant shrew: any of 15 species of rat-sized African mammals named for their long, tapered, and flexible snout (proboscis). All have slim bodies, slender limbs, and very long hind legs and feet. ...
elephant's-foot: an odd-looking twining plant of the yam family (Dioscoreaceae), characterized by a large, woody, and partially exposed tuber. It is native to semiarid areas in southern Africa. The tubercle-covered tuber, ...
Elephanta Island: island located in Bombay Harbour of the Arabian Sea, about 6 miles (10 km) east of Bombay (Mumbai) city and 2 miles (3 km) west of the mainland coast of ...
elephantiasis: condition associated with the infectious diseases known collectively as filariasis (q.v.).
Elephantine: island in the Nile opposite Aswan city in Aswan muhafazah (governorate), Upper Egypt. Elephantine is the Greek name for pharaonic Abu. There the 18th- and 19th-dynasty pharaohs built a large ...
elephantsnout fish: any of certain mormyrid (q.v.) species.
Eleusinia: ancient Greek festival in honour of Demeter (the goddess of agriculture), unconnected with the Eleusinian Mysteries despite the similarity of names. The Eleusinia, which included games and contests, was held ...
Eleusinian Mysteries: most famous of the secret religious rites of ancient Greece. According to the myth told in the Homeric Hymn to Demeter, the earth goddess Demeter (q.v.) went to Eleusis in ...
eleusis: card game invented by Robert Abbott and first described in Martin Gardner's "Mathematical Games" column in Scientific American (July 1959). A more-refined version appeared in Abbott's
Eleusis: ancient Greek city famous as the site of the Eleusinian Mysteries. Situated in the fertile plain of Thria about 14 miles (23 km) west of Athens, opposite the island of ...
Eleutherius, Saint: pope from about 175 to 189. During his pontificate the church was involved in a controversy over Montanism, a movement that arose in Asia Minor among Christians who believed that ...
elevated transit line: railroad line, usually electric, raised above the ground or street level, usually on a trestle, for local transit in urban areas. By the mid-19th century it was evident that surface ...
elevator: car that moves in a vertical shaft to carry passengers or freight between the levels of a multistory building. Most modern elevators are propelled by electric motors, with the aid ...
eleven-plus: in England, competitive examination given between primary and secondary school at about age 11. It evolved after 1944 as a means of determining in which of the three types of ...
elf: in Germanic folklore, originally, a spirit of any kind, later specialized into a diminutive creature, usually in tiny human form. In the Prose, or Younger, Edda, elves were classified as ...
Elf Aquitaine: (French: "Elf Aquitaine National Society"), French corporate group formed on Sept. 1, 1976, in the reorganization and consolidation of petrochemical, mining, and several other industries. Until 1994, a French-government company, ...
elf owl: (Micrathene whitneyi), tiny bird of prey of the family Strigidae (order Strigiformes) of Mexico and the southwestern United States. It is the smallest owl and is about the size of ...
elfin woodland: stunted forest at high elevations in warm, moist areas. Its low, gnarled trees are heavily draped with air plants, and its floor is cushioned by mosses and other primitive plants. ...
Elgar, Sir Edward: English composer whose works in the orchestral idiom of late 19th-century Romanticism-characterized by bold tunes, striking colour effects, and mastery of large forms-stimulated a renaissance of English music.
Elgin: city, Kane and Cook counties, northeastern Illinois, U.S. It lies on the Fox River, about 40 miles (65 km) northwest of downtown Chicago. Potawatomi Indians were early inhabitants of the ...