Electrode potential Potential of a cell assembled of two electrodes can be determined from the two individual electrode potentials using or, equivalently, This follows from the IUPAC definition of the electric potential difference of a galvanic cell, according to which the electric potential difference of a cell is the difference of the potentials of the electrodes on the right and the left of the galvanic cell. When Δ"V" is positive, then positive electrical charge flows through the cell from the left electrode (anode) to the right electrode (cathode). Electrode potential Electrode potential, "E", in chemistry or electrochemistry, according to a IUPAC definition,
Plate electrode tube envelope and is cooled by radiation cooling, forced air or water. A problem in early vacuum tubes was "secondary emission"; electrons striking the plate could knock other electrons out of the metal surface. In some tubes such as tetrodes these "secondary electrons" could be absorbed by other electrods such as grids in the tube, resulting in a current out of the plate. This current could cause the plate circuit to have negative resistance, which could cause unwanted parasitic oscillations. To prevent this most plates in modern tubes are given a chemical coating which reduces secondary emission. Plate electrode A