Use of a Switch
To open and close the path of current easily and safely, we use a switch. These are the switches which make it possible for us to OFF and ON our household electrical appliances safely. We can see in the above activity that in a closed circuit current passes through a certain type of material while through some other type of material it cannot pass. The materials which allow current to pass through them are called conductors and the materials which do not allow current to pass through them are called insulators. Metallic objects are usually conductors and materials like plastic, dry wood, glass and rubber are insulators.