Electric Conductors

The material which allows the flow of electrical current are called electric conductors. Generally metals are good conductors of electricity and metals such as copper and aluminum are the most commonly used.

In conductors the electrons are the charge carriers. The electrons move freely from
one atom and offer low resistance to the flow of current. The outermost electrons in the atoms are so loosely bound and at room-temperature they move randomly in the space between the atoms of that material. These electrons leave their atom and float around in the space between adjacent atoms. This relative mobility of electrons within a material is known as conductivity. Materials with high electron mobility are called conductors, while materials with low electron mobility are called insulators. An insulator has very few charge carriers and doesn’t conduct electricity. Insulators offer very high resistance to current.

Electricity Conducting Materials

Silver: Silver is the best conducting metal in the world, but is very expensive and not practical to be used. But it is used in some specialized equipment such as satellites.

Copper: copper has a high conductivity and it is the most widely used conductor in electrical appliances. Annealed copper is treated as international standard to which the conductivity of all other electrical conductors is compared.

Aluminum: Aluminum has 61% of the conductivity of copper but is being used in wiring owing to its lower cost. Aluminum has a different coefficient of thermal expansion compared to the other materials used for connections. This loosens the connections. Aluminum is also the most common metal used in high-voltage transmission lines, in combination with steel.

Water: Pure water is not an electrical conductor but a small amount of impurities, such as salt, transforms it into a conductor.

Apart from these below are the other types of conductors:

·         Gold

·         Iron

·         Steel

·         Brass

·         Bronze

·         Mercury

·         Graphite

Effect of Temperature on Conductivity:

Some materials experience changes in their electrical properties under different conditions. For example Gases such as air is normally an insulating medium but it will become conductive if heated to a very high temperature. The metals which are good conductors at room temperature become poor conductors of electricity when heated.

Also Read:

Electricity
Electric Charge
Electric Current
Resistor