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magnetism

(Encyclopedia)CE5 Lines of induction around a single bar magnet and between opposite poles of different magnets magnetism, force of attraction or repulsion between various substances, especially those made of i...

telephone

(Encyclopedia)CE5 Hand telephone telephone, device for communicating sound, especially speech, usually by means of wires in an electric circuit. The telephones now in general use evolved from the device invente...

Bristol, cities, United States

(Encyclopedia)Bristol. 1 Industrial city (2020 pop. 60,833), Hartford co., central Conn., on the Pequabuck River; settled 1727, inc. 1785. Its clock-making ...

electron tube

(Encyclopedia)CE5 Triode electron tube electron tube, device consisting of a sealed enclosure in which electrons flow between electrodes separated either by a vacuum (in a vacuum tube) or by an ionized gas at l...

Albany, cities, United States

(Encyclopedia)Albany 1, 3, 4 ôlˈbənē; 2 ôlˈbĕnˌē, ălbāˈnē [key]. 1 Residential city (2020 pop. 20,271), Alameda co., W Calif., on the eastern shore of San Francisco...

fencing

(Encyclopedia)fencing, sport of dueling with foil, épée, and saber. Swords have been in use since the Bronze Age, and nearly all people of antiquity practiced swordsmanship. Fencing as a contest has existed at ...

molybdenum

(Encyclopedia)molybdenum məlĭbˈdənəm [key] [Gr.,=leadlike], metallic chemical element; symbol Mo; at. no. 42; at. wt. 95.96; m.p. about 2,617℃; b.p. about 4,612℃; sp. gr. 10.22 at 20℃; valence +2, +3, +4...

loom

(Encyclopedia)loom, frame or machine used for weaving; there is evidence that the loom has been in use since 4400 b.c. Modern looms are of two types, those with a shuttle (the part that carries the weft through the...

cellular telephone

(Encyclopedia)cellular telephone or cellular radio, telecommunications system in which a portable or mobile radio transmitter and receiver, or “cellphone,” is linked via microwave radio frequencies to base tran...

electron

(Encyclopedia)electron, elementary particle carrying a unit charge of negative electricity. Ordinary electric current is the flow of electrons through a wire conductor (see electricity). The electron is one of the ...