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[′vōlt ′am‚pir]
The unit of apparent power in the International System; it is equal to the apparent power in a circuit when the product of the root-mean-square value of the voltage, expressed in volts, and the root-mean-square value of the current, expressed in amperes, equals 1. Abbreviated VA.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



a unit of full power of an alternating current, designated by VA. The full power of an alternating current is defined as the product of the effective values of the current in a circuit (in amperes) and the voltage at its terminals (in volts). The effective values of the current and voltage are measured by AC ammeters and voltmeters . The concept of full power is distinct from the real power of an electric circuit, which is expressed in watts and equals UI cos φ where φ is the angle of displacement of the phases between voltage U and current I, and as distinct from the reactive power, equal to UI sin φ and expressed in vars.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
All electric usage will be reduced in watts per sq ft (volt-amperes x power factor per sq ft).
The Secretary EAD said, "Success of the project depends on effective and timely implementation; therefore, we will continue to focus on timely completion of the power distribution enhancement projects." According to a senior Project Officer at ADB Pakistan, the project would add 1,881 mega volt-amperes (MVA) of transformer capacity, 791 kilometers (km) of new transmission lines and up-gradation of 399 km of the existing transmission lines, which would bring stability in the distribution network.