Ampere W/V. Current can be measured by a multimeter, a device that can measure electrical voltage, current, and resistance. The standard ampere is most accurately realized using a Kibble balance, but is in practice maintained via Ohm's law from the units of electromotive force and resistance, the volt and the ohm, since the latter two can be tied to physical phenomena that are relatively easy to reproduce, the Josephson junction and the quantum Hall effect, respectively. At present, techniques to establish the realization of an ampere have a relative uncertainty of approximately a few parts in 10, and involve realizations of
Electrode potential electrode component. In a cell, there is an electrode potential for the cathode and an electrode potential for the anode. The difference between the two electrode potentials equals the cell potential: The measured electrode potential may be either that at equilibrium on the working electrode ("reversible potential"), or a potential with a non-zero net reaction on the working electrode but zero net current ("corrosion potential", "mixed potential"), or a potential with a non-zero net current on the working electrode (like in galvanic corrosion or voltammetry). Reversible potentials can be sometimes converted to the standard electrode potential for a given electroactive