Part of the Electronics glossary:

An electrical conductor is a substance in which electrical charge carriers, usually electrons, move easily from atom to atom with the application of voltage. Conductivity, in general, is the capacity to transmit something, such as electricity or heat. 

Pure elemental silver is the best electrical conductor encountered in everyday life. Copper, steel, gold, aluminum, and brass are also good conductors. In electrical and electronic systems, all conductors comprise solid metals molded into wires or etched onto circuit boards.

Some liquids are good electrical conductors. Mercury is an excellent example. A saturated salt-water solution acts as a fair conductor. Gases are normally poor conductors because the atoms are too far apart to allow a free exchange of electrons. However, if a sample of gas contains a significant number of ions, it can act as a fair conductor.

A substance that does not conduct electricity is called an insulator or dielectric material. Common examples include most gases, porcelain, glass, plastic, and distilled water. A material that conducts fairly well, but not very well, is known as a resistor. The most common example is a combination of carbon and clay, mixed together in a specific ratio to produce a constant and predictable opposition to electric current

Substances called semiconductors act as good conductors under some conditions and poor conductors under other conditions. Silicon, germanium, and various metal oxides are examples of semiconductor materials. In a semiconductor, both electrons and so-called holes (electron absences) act as charge carriers.

At extremely low temperatures, some metals will conduct electricity better than any known substance at room temperature. This phenomenon is called superconductivity, and a substance that behaves that way is called a superconductor.

This was last updated in May 2012
Contributor(s): Stan Gibilisco
Posted by: Margaret Rouse

Related Terms

Definitions

  • frequency jammer

    - Frequency jamming is the disruption of radio signals through use of an over-powered signal in the same frequency range. When most people think of frequency jamming, what comes to mind are radio, r... (WhatIs.com)

  • anode

    - An anode is the electrode in a polarized electrical device through which current flows in from an outside circuit. Conversely, a cathode is the eletrode in a polarized electrical device through whi... (WhatIs.com)

  • cathode

    - A cathode is the metallic electrode through which current flows out in a polarized electrical device. Conversely, an anode is the electrode in a polarized electrical device through which current fl... (WhatIs.com)

Glossaries

  • Electronics

    - Terms related to electronics, including definitions about electrical components and words and phrases about computers, laptops parts, digital cameras, televisions and home appliances.

  • Internet applications

    - This WhatIs.com glossary contains terms related to Internet applications, including definitions about Software as a Service (SaaS) delivery models and words and phrases about web sites, e-commerce ...

Ask a Question. Find an Answer.Powered by ITKnowledgeExchange.com

Ask An IT Question

Get answers from your peers on your most technical challenges

Ask Question

Tech TalkComment

Share
Comments

    Results

    Contribute to the conversation

    All fields are required. Comments will appear at the bottom of the article.