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Sprague, Frank Julian

(Encyclopedia)Sprague, Frank Julian sprāg [key], 1857–1934, American electrical engineer, b. Milford, Conn., grad. Annapolis, 1878. He was an assistant to Thomas Edison in 1883 and independently created a superi...

electric-light bug

(Encyclopedia)electric-light bug: see water bug. ...

Lenz's law

(Encyclopedia)Lenz's law, physical law, discovered by the German scientist H. F. E. Lenz in 1834, that states that the electromotive force (emf) induced in a conductor moving perpendicular to a magnetic field tends...

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...

Galion

(Encyclopedia)Galion gălˈyən [key], city (2020 pop. 10,453), Crawford co., N central Ohio; inc. as a bor...

electric and magnetic units

(Encyclopedia)electric and magnetic units, units used to express the magnitudes of various quantities in electricity and magnetism. Three systems of such units, all based on the metric system, are commonly used. On...

Hickory, city, United States

(Encyclopedia)Hickory, city (2020 pop. 43,490), Burke and Catawba counties, W N.C., at the foot of the Blue Ridge Mts.; inc. 1870. It is a processing and trade center...

vacuum cleaner

(Encyclopedia)vacuum cleaner, mechanical device using a draft of air to remove dust, loose dirt, or other particulate matter from dry surfaces. It is especially useful on highly textured surfaces, such as carpets a...

electromagnet

(Encyclopedia)CE5 Electromagnet electromagnet, device in which magnetism is produced by an electric current. Any electric current produces a magnetic field, but the field near an ordinary straight conductor is ...

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...