Electrical circuit laws turn component relationships and network connections into equations for voltage, current, resistance, power and energy. The articles below cover Ohm’s law, Kirchhoff’s current and voltage laws, electromagnetic laws, electrostatic laws and Joule’s heating law.
Choose a sign convention before writing circuit equations. Kirchhoff’s current law expresses charge conservation at a node, while Kirchhoff’s voltage law applies around a closed loop under the lumped-circuit assumptions. Ohm’s law then relates voltage and current for an ohmic element, and Joule’s law gives its rate of electrical energy conversion to heat.
