Conductors and Insulators

Electricity of Class 10

CONDUCTORS:

Those substances through which electric charges can flow, are called conductors and the flow of electric charges is called electricity. All the metals like silver, copper and aluminium etc., are conductors. Carbon, in the form of graphite, is a conductor and the aqueous solutions (water solutions) of salts are also conductors. The human body is a fairly good conductor. All the conductors (like metals) have some electrons which are loosely held by the nucleus of their atoms. These electrons are called "free electrons" and can move from one atom to another atom throughout the conductor. The presence of "free electrons" in a substance makes it a conductor of electricity.

INSULATORS:

Those substances through which electric charges cannot flow, are called insulators. In other words, those substances through which electricity cannot flow, are called insulators. Glass, ebonite, rubber, most of the plastics, paper, dry wood„ cotton, mica, bakelite, and dry air, are all insulators because they do not allow electric charges (or electricity) to flow through them. In the case of charged insulators like glass, ebonite etc., the electric charges remain bound to them and do not move away. The electrons present in insulators are strongly held by the nuclei of their atoms. Since there are "no free electron" in an insulator which can move from one atom to another, so an insulator does not allow electric charges (or electricity) to flow through it.