elector German Kurfurst. Prince of the Holy Roman Empire who had a right to participate in electing the German emperor. Beginning c. 1273, and with the confirmation of the Golden Bull, there were seven electors: the archbishops of Trier, Mainz, and Cologne; the duke of Saxony; the count palatine of the Rhine; the margrave of Brandenburg; and the king of Bohemia. Other electorates were created much later for Bavaria (1623— 1778), Hanover (1708), and Hesse-Kassel (1803), but by the 17th century the electors’ office had become meaningless because the Habsburg dynasty produced the de facto emperors. The office disappeared when the empire was abolished in 1806.
electoral college Constitutionally mandated process for electing the U.S. president and vice president. Each state appoints as many electors as it has senators and representatives in Congress (U.S. senators, represen¬ tatives, and government officers are ineligible); the District of Columbia has three votes. A winner-take-all rule operates in every state except Maine and Nebraska. Three presidents have been elected by means of an electoral college victory while losing the national popular vote (Ruther¬ ford B. Hayes in 1877, Benjamin Harrison in 1888, and George W. Bush in 2000). Though pledged to vote for their state’s winners, electors are not constitutionally obliged to do so. A candidate must win 270 of the 538 votes to win the election.
Electoral Commission (1877) Commission created to resolve the disputed 1876 presidential election between Republican Rutherford B. Hayes and Democrat Samuel Tilden. Tilden had won the popular vote and was only one electoral vote short of victory, but the Republicans contested the tallies in four states, charging fraud. Unable to reach a consensus, Congress appointed a 15-member commission, evenly divided between the two parties, except for one justice, Joseph R Bradley, a Republican considered nonpartisan; Republicans pressured him, and the tally went to Hayes, who was declared the winner on March 2. See also Wormley Con¬ ference.
electoral system Method and rules of counting votes to determine the outcome of elections. Winners may be determined by a plurality, a major¬ ity (more than 50% of the vote), an extraordinary majority (a percentage of the vote greater than 50%), or unanimity. Candidates for public office may be elected directly or indirectly. Proportional representation is used
European red elder (Sambucus race- mosa).
AJ. HUXLEY
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Electro ► electric shock I 607
in some areas to ensure a fairer distribution of legislative seats to con¬ stituencies that may be denied representation under the plurality or major¬ ity formulas. See also party system, plurality system, primary election.
Electra In Greek legend, the daughter of Agamemnon and Clytemnestra. When Agamemnon was murdered by Clytemnestra and her lover Aegis- thus, Electra saved her young brother Orestes from the same fate by send¬ ing him away. Orestes later returned, and Electra helped him kill their mother and Aegisthus. She then married her brother’s friend Pylades. The story is treated in plays by Aeschylus, Sophocles, and Euripides.
Electra complex See Oedipus complex
electric automobile Battery-powered motor vehicle. Originating in the 1880s, electric cars were used for private passenger, truck, and bus transportation in cities, where their low speeds and limited battery range were not drawbacks, and the cars became popular for their quietness and low maintenance costs. Until 1920 they were competitive with gasoline- fueled cars; they became less so after the electric self-starter made gasoline-powered cars more attractive and mass production made them cheaper to produce. In Europe electric vehicles have been used as short- range delivery vans. Renewed interest in electric cars beginning in the 1970s, spurred especially by new consciousness of foreign oil dependency and environmental concern, led to improvements in speed and range. Recent laws, particularly in California, have mandated commercial pro¬ duction. “Hybrid” cars employing both electric and internal combustion engines and providing the best features of both technologies, have recently become commercially available. Experimental vehicles have used solar FUEL CELLS.
electric charge Quantity of electricity that flows in electric currents or that accumulates on the surfaces of dissimilar nonmetallic substances that are rubbed together briskly. It occurs in discrete natural units, equal to the charge of an electron or proton. It cannot be created or destroyed. Charge can be positive or negative; one positive charge can combine with one negative charge, and the result is a net charge of zero. Two objects that have an excess of the same type of charge repel each other, while two objects with an excess of opposite charge attract each other. The unit of charge is the coulomb, which consists of 6.24 x 10 18 natural units of elec¬ tric charge.
electric circuit See circuit
electric current Movement of electric charge carriers. In a wire, elec¬ tric current is a flow of electrons that have been dislodged from atoms and is a measure of the quantity of electrical charge passing any point of the wire per unit time. Current in gases and liquids generally consists of a flow of positive ions in one direction together with a flow of negative ions in the opposite direction. Conventionally, the direction of electric current is that of the flow of the positive ions. In alternating current (AC) the motion of the charges is periodically reversed; in direct current (DC) it is not. A common unit of current is the ampere, a flow of one coulomb of charge per second, or 6.24 x 10 18 electrons per second.
electric dipole VdI-pol\ Pair of equal and opposite electric charges, the centres of which do not coincide. An atom in which the centre of the negative cloud of electrons has been shifted slightly away from the nucleus by an external electric field is an induced electric dipole. When the exter¬ nal field is removed, the atom loses its dipolarity. A water molecule, in which two hydrogen atoms are situated to one side of an oxygen atom, is a permanent electric dipole. The oxygen side is always slightly negative, the hydrogen side slightly positive.
electric discharge lamp o/ vapor lamp Lighting device consist¬ ing of a transparent container within which a gas is energized by an applied voltage and made to glow. After practical generators were devised in the 19th century, many experimenters applied electric power to tubes of gas. From c. 1900, electric discharge lamps were in use in Europe and the U.S. Fluorescent, neon, mercury, sodium, and metal-halide lamps are of the electric discharge variety.
electric eel Eel-shaped South American fish (Electrophones electricus ) capable of producing an electric shock strong enough to stun a human. The electric eel (not a true eel) is a sluggish inhabitant of slow freshwater, sur¬ facing periodically to gulp air. Long, cylindrical, scaleless, and gray- brown, it sometimes reaches a length of 9 ft (2.75 m) and a weight of 49 lbs (22 kg). The tail region, bordered below by a long anal fin that the fish
undulates to move about, contains the electric organs. The shock (up to 650 volts discharged at will) is used mainly to immobilize fish and other prey.
electric eye See photocell
electric field Region around an electric charge in which an electric force is exerted on another charge. The strength of an electric field E at any point is defined as the electric force F exerted per unit positive electric charge q at that point, or E = F/q. An electric field has both magnitude and direction and can be represented by lines of force, or field lines, that start on positive charges and terminate on negative charges. The electric field is stronger where the field lines are close together than where they are farther apart. The value of the electric field has dimensions of force per unit charge and is measured in units of newtons per coulomb.