Edison effect The flow of an current through a laboratory vacuum, between two metal wires, one of which is heated. The current flows only when the heated wire is more negative, because it is carried by free electrons released from the wire by its heat. The Edison effect was the principle behind "vacuum tubes" used in radio and television receivers and transmitters before the invention of the transistor. Related category • ELECTRICITY AND MAGNETISM Source: NASA Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) |