Electrical network equations

The analysis of electrical circuits is based on the application of two essential laws of physics originally proposed by the German physicist Gustav Kirchhoff in 1845. These laws, which can be applied in both the time and frequency domains, may be considered as particular cases of Maxwell equations (which would be proposed 20 years later). Both laws are described in the following considering only their formulation in the time domain (nevertheless, they can be applied in the same form to phasor analysis at any given frequency). Beforehand, some basic definitions related with circuit topology are introduced.