Kirchhoff’s current law and voltage law, defined by Gustav Kirchhoff, describe the relation of values of currents that flow through a junction point and voltages in an electrical circuit loop, in an electrical circuit.
Kirchhoff’s Current Law (KCL)
This is Kirchhoff’s first law.
The sum of all currents that enter an electrical circuit junction is 0. The currents enter the junction have the positive sign and the currents that leave the junction have a negative sign: