The answer is The ability to carry power across long distances. The movement of electrical current is constantly reversing direction.AC current reverses direction 60 times per second. It is very easy to adjust the voltage of AC using a device known as a transformer. Power companies can transmit power at extremely high voltage levels and then transform the voltage down to 120 volts inside the house. The ability to carry power across long distances was the most important advantage of AC over DC.
