alternating current
noun
an electric current that reverses direction at regular intervals, having a magnitude that varies continuously in sinusoidal manner. Abbreviation: ac
Compare
direct current.
Origin of alternating current
First recorded in 1830–40
Words nearby alternating current
Example sentences from the Web for alternating current
British Dictionary definitions for alternating current
alternating current
noun
a continuous electric current that periodically reverses direction, usually sinusoidally
Abbreviation: AC Compare: direct current
Scientific definitions for alternating current
alternating current
[ ôl′tər-nā′tĭng ]
An electric current that repeatedly changes its direction or strength, usually at a certain frequency or range of frequencies. The term is also used to describe alternating voltages. Power stations generate alternating current because it is easy to raise and lower the voltage of such current using transformers; thus the voltage can be raised very high for transmission (high voltages lose less power as heat than do low voltages), and lowered to safe levels for domestic and industrial use. In North America, the frequency of alternation of the direction of flow is 60 Hz, or 60 cycles per second. In other parts of the world it is 50 Hz. Compare direct current. See Notes at current Tesla.
Cultural definitions for alternating current
alternating current
An electric current (see also current) in which the flow reverses periodically. (Compare direct current (DC).)
notes for alternating current
In the United States, most household current is AC, going through sixty reversal cycles each second. Electric motors in household appliances are designed to work with current at this rate of reversal.