Do wires degenerate when electric current is passed through them? I mean, do they lose matter after continued use?

Asked by: Creative Genius

Answer

Wires made from metals all conduct electric current by the motion of electrons. Electrons move in (or out) of one end of a wire, and an equal number move out (or in) the other end. This balance is maintained by extremely powerful electric forces. No net amount of matter is ever transferred when current flows.

Two effects may occur during high current flow: 1) the wire may become overheated to the point that surface oxidation or even evaporation may take place, 2) at the connection points at each end of the wire, especially if the terminations are of a different type of metal than the wire, some atoms may migrate into or out of the wire.

Under normal current flow, there is no significant loss of matter in a wire. Only in the extreme case of overheating will the wire be degraded or even destroyed by melting.

The tungsten filament of an incandescent light is an example of a wire under extreme conditions. Eventually all filaments will fail due to the high temperature of operation. If the bulb is cracked, the filament will be exposed to oxygen and immediately be oxidized or 'burn out.'
Answered by: S. Wilber, President, ComScire - Quantum World Corporation