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Ohm's law

(Encyclopedia)Ohm's law ōm [key] [for G. S. Ohm], law stating that the electric current i flowing through a given resistance r is equal to the applied voltage v divided by the resistance, or i=v/r. For general app...

Ohm, Georg Simon

(Encyclopedia)Ohm, Georg Simon gāˈôrkh zēˈmôn ōm [key], 1787–1854, German physicist. He was professor at Munich from 1852. His study of electric current led to his formulation of the law now known as Ohm's...

ohm

(Encyclopedia)ohm ōm [key] [for G. S. Ohm], symbol Ω, unit of electrical resistance, defined as the resistance in a circuit in which a potential difference of one volt creates a current of one ampere; hence, 1 oh...

resistance, in electricity

(Encyclopedia)resistance, property of an electric conductor by which it opposes a flow of electricity and dissipates electrical energy away from the circuit, usually as heat. Optimum resistance is provided by a con...

ohmmeter

(Encyclopedia)ohmmeter ōmˈmēˌtər [key], instrument used to measure the electrical resistance of a conductor. It is usually included in a single package with a voltmeter, and often an ammeter. In normal usage, ...

electricity

(Encyclopedia) CE5 Electrical and radio symbols electricity, class of phenomena arising from the existence of charge. The basic unit of charge is that on the proton or electron—the proton's charge is designate...

Rowland, Henry Augustus

(Encyclopedia)Rowland, Henry Augustus rōˈlənd [key], 1848–1901, American physicist, b. Honesdale, Pa., grad. Rensselaer Polytechnic Institute, 1870. He was professor of physics at Johns Hopkins from 1875. Rowl...

galvanometer

(Encyclopedia) CE5 Galvanometer galvanometer gălˌvənŏmˈətər [key], instrument used to determine the presence, direction, and strength of an electric current in a conductor. All galvanometers are based upo...

law

(Encyclopedia)law, rules of conduct of any organized society, however simple or small, that are enforced by threat of punishment if they are violated. Modern law has a wide sweep and regulates many branches of cond...

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...
 

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