current (I) The flow of electrons through a metallic circuit, like the flow of water down a riverbed.The direction of flow is from positive (+) pole to negative (–) pole at opposite ends of the circuit. Direct current (DC) travels in one direction, only. Alternating current (AC) travels first in one direction and then in the other as the polarity changes at the ends of the circuit. Current is measured in amperes (A), or amps. |