Váltóáram

Váltóáram, often abbreviated as AC, is an electric current which periodically reverses direction, in contrast to direct current (DC) which flows only in one direction. This reversal of direction is typically achieved by an alternating voltage. The most common waveform for alternating current is a sinusoidal wave, but other shapes such as square or triangular waves are also used. The frequency of the alternating current refers to the number of cycles the current completes in one second, measured in Hertz (Hz). In most of the world, the standard frequency for power grids is 50 Hz, while in North America it is 60 Hz.

The primary advantage of alternating current over direct current is its ability to be easily transformed to different voltage levels. This is achieved using transformers, which are devices that can step up or step down voltage. This property is crucial for efficient long-distance power transmission. High voltages are used to transmit electricity over long distances to minimize energy loss due to resistance in the wires. Before reaching consumers, these high voltages are stepped down to safer and more usable levels. Alternating current is the standard for electricity distribution in power grids worldwide due to these transmission efficiencies. It is also the type of electricity supplied to most homes and businesses.