CBSE Class 10 Answered

The earth is made up of materials that is electrically conductive. A fault current will flow to 'earth' through the live conductor, provided it is earthed .  This is to prevent a potentially live conductor from rising above the safe level .  All exposed metal parts of an electrical installation or electrical appliance must be earthed .

            The main objectives of the earthing are to :

   1) Provide an alternative path for the fault current to flow so that it will not endanger the user

   2) Ensure that all exposed conductive parts do not reach a dangerous potential