cathode(redirected from Copper cathode)
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terminal through which electric current passes between metallic and nonmetallic parts of an electric circuit. In most familiar circuits current is carried by metallic conductors, but in some circuits the current passes for some distance through a nonmetallic conductor.
..... Click the link for more information. through which current leaves an electric device. In electrolysiselectrolysis
, passage of an electric current through a conducting solution or molten salt that is decomposed in the process. The Electrolytic Process
The electrolytic process requires that an electrolyte, an ionized solution or molten metallic salt, complete an
..... Click the link for more information. , it is the negative electrode in the electrolytic cell.
(1) In an electron tube or a gas-discharge tube, the electrode that is the source of electrons that ensure the conductivity of interelectrode space in a vacuum or maintain the steadiness of the passage of an electric current through the gas. Depending on the mechanism of emission of electrons, there exist thermionic cathodes, photocathodes, and cold cathodes.
(2) The negatively charged electrode (pole) of a source of current (galvanic cell, storage battery).
(3) The electrode of an electrolytic cell, an electric arc, and other similar devices that are connected to the negative pole of a source of current.
cathodeThe terminal on a device that emits current. In the cathode ray tubes (CRT) of the bulky TVs and monitors prior to flat panels, the negative cathode emits electrons that are attracted to the positive "anode." Current flows out of cathodes and into anodes. Depending on the application, a cathode may be considered positive or negative. Derived from Greek, cathode and anode mean "down" and "up" respectively. See electrode and cold cathode.
|In vacuum tubes, the cathodes are the emitters, and the anodes are the collectors.|