Volta potential by its work function, and so dissimilar metals can show an electric potential difference even at equilibrium. The Volta potential is "not" an intrinsic property of the two bulk metals under consideration, but rather is determined by work function differences between the metals' surfaces. Just like the work function, the Volta potential depends sensitively on surface state, contamination, and so on. The potential is given by the formula: formula_1, where V is the potential, The Volta potential can be significant (of order 1 volt) but it cannot be measured directly by an ordinary voltmeter. A voltmeter does not measure vacuum
Equivalent series resistance models, however simple or complex, can be inserted into a circuit to calculate performance. Computer tools are available for complex circuits; e.g., the SPICE program and its variants. An inductor consists of a conducting insulated wire coil usually wound around a ferromagnetic core. Inductors have resistance inherent in the metal conductor, quoted as DCR in datasheets. This metallic resistance is small for small inductance values (typically below 1 Ω). The DC wire resistance is an important parameter in transformer and general inductor design because it contributes to the impedance of the component, and current flowing through that resistance is dissipated