Physics - Conductors and Insulators

Conductors - 1. The materials which allow the electric current or heat to pass through it. 2. The electrons in a conductor can freely move. 3. Will become charged only if held with insulating handle or charge transfer to earth thru human body. 4. Silver is the best conductor. Eg. Copper, Aluminium, silver, mercury

Insulators - 1. The materials which do not allow the electric current or heat to pass through it 2. the covalent bond between the atoms are very strong, electrons do not move freely. 3. Although can be charged by rubbing, charge cannot move from place of occurrence due to static electric charge. 4. Eg. wood, paper, porcelain, etc. Graphite is the only non-metal that can conduct electricity.

Semiconductors -Has electrical properties between that of a conductor and insulator. Used for the preparation of solid state devices like diode, transistor, etc. Eg. Germanium, Silicon, etc.