ACjännitteisiin

ACjännitteisiin refers to alternating voltage in Finnish. Alternating voltage is an electric potential that periodically reverses direction. Unlike direct voltage (DC), where the voltage polarity remains constant, AC voltage oscillates, typically in a sinusoidal pattern. This oscillation means that the voltage rises to a peak in one direction, falls through zero, reaches a peak in the opposite direction, and then returns to zero, repeating the cycle.

The key characteristic of AC voltage is its frequency, measured in Hertz (Hz), which indicates the number of complete cycles per second. In many parts of the world, household electricity is supplied at a frequency of 50 Hz or 60 Hz. The magnitude of AC voltage is often described by its root mean square (RMS) value, which is equivalent to the DC voltage that would produce the same amount of heat in a resistive load.

AC voltage is fundamental to modern electrical power systems. It is generated by alternators and can be easily transformed to higher or lower voltages using transformers. This ability to efficiently change voltage levels is a major advantage of AC over DC, allowing for the transmission of electricity over long distances at high voltages (reducing current and thus resistive losses) and then stepping it down to safer, usable levels for homes and businesses. Examples of AC voltages include the standard mains voltage supplied to homes and the voltage found in car alternators.