cathode

A cathode is an electrode through which (positive) electric current flows out of a polarized electrical device. Mnemonic: CCD (Cathode Current Departs). To dispel a common misconception, often incorrectly inferred from the correct fact that in all electrochemical devices positively charged cations move towards the cathode and/or negatively charged anions move away from it, cathode polarity is not always negative but depends on the device type, and sometimes even in which mode it operates, as determined by the above current direction based universal definition. Examples:In a discharging battery or galvanic cell (drawing) the cathode is the positive terminal, where conventional current flows out. This outwards current is carried internally by positive ions moving from the electrolyte to the positive cathode (chemical energy is responsible for this "uphill" motion). It is continued externally by electrons moving inwards, negative charge moving one way amounting to positive current flowing the other way.In a recharging battery, or an electrolytic cell, the cathode is the negative terminal, which sends current back to the external generator.In a diode, it is the negative terminal at the pointed end of the arrow symbol, where current flows out of the device. Note electrode naming for diodes is always based on the direction of the forward current (that of the arrow, in which the current flows "most easily"), even for types such as zener diodes or solar cells where the current of interest is the reverse current.In a cathode ray tube, it is the negative terminal where electrons flow in, i.e. where current flows out of the device.
See more at Wikipedia.org...

La cathode d'un appareil passif parcouru par un courant continu est l'électrode d'où sort le courant. Pour une résistance, c'est l'électrode connectée au pôle négatif du générateur.
Pour la suite, voir Wikipédia.org…

Eine Kathode [] (von agr.  kathodos, „Weg nach unten“) ist allgemein der Minuspol, also die Elektrode, die Elektronen über den elektrischen Anschluss aufnimmt und Richtung Anode weitergibt. Die Kathode (-) ist die Gegenelektrode zur Anode (+). Kationen (+) wandern zur Kathode und Anionen (-) zur Anode.
Mehr unter Wikipedia.org...

Katoda to elektroda z której do układu dostaje się ładunek ujemny, lub jest absorbowany ładunek dodatni. W zależności od charakteru układu lub urządzenia elektrycznego (kierunku przepływającego przez nie prądu elektrycznego), katoda może być elektrodą dodatnią lub ujemną. Katoda występuje zawsze w parze z elektrodą jej przeciwną pod względem znaku, czyli anodą.
W celu uzyskania więcej informacji, zobacz w Wikipedia.οrg...

Nei sistemi elettrochimici, il catodo è l'elettrodo sul quale avviene una reazione di riduzione.Nel caso di una pila, la riduzione avviene spontaneamente e consuma elettroni, quindi il catodo è il polo positivo.Nel caso di una cella elettrolitica, la riduzione viene forzata somministrando elettroni, quindi il catodo è il polo negativo.
Per saperne di più visita Wikipedia.org...