Resistors take electrical energy and convert it to heat.
Also see the discussion of complex impedance below. Also see the discussion of complex impedance below. Kirchoff's Current Law states that the algebraic sum of all currents entering and leaving a node is zero . A node is defined as a point in an electrical circuit where three or more wires are joined together. The currents entering the node are considered to be positive in the equation above, while the currents leaving the node are considered to be negative .