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
Zero-ohm link resistors can be useful as configuration jumpers, but caution is exercised for PCB designs which may use zero-ohm resistors to select between options which require larger trace currents in the design. For these situations, it is better design practice to specify a low-ohm resistance, such as a 0.001-ohm to 0.003-ohm resistor, rather than the generic "zero-ohm" resistor in which the actual resistance may be higher, and tolerance is not given. The low-ohm resistors are easily obtained with 5% or 1% tolerances on a maximum specified resistance and can be safely utilized to pass much higher currents. For example, a surface-mounted