ABSTRACT
This chapter states Kirchhoff's laws and demonstrates how unknown currents and voltages may be evaluated in series/parallel circuits. Complex direct current (DC) circuits cannot always be solved by Ohms law and the formulae for series and parallel resistors alone. For these types of calculations people need certain rules which allow to obtain the circuit equations and for this they can use Kirchhoff's laws. Kirchhoff developed two laws which further help the determination of unknown currents and voltages in DC series/parallel networks. Kirchhoff's current law states that at any junction in an electric circuit the total current flowing towards that junction is equal to the total current flowing away from the junction. Kirchhoff's voltage law state that, in any closed loop in a network, the algebraic sum of the voltage drops taken around the loop is equal to the resultant electro motive force (EMF) acting in that loop.
