electric appliances like electric-press ,toaster ,fans etc.are connected to electric mains through three-pin plug.Why?
Three pin plug consists of three pins and it is used to connect three wires; live wire, neutral wire and earth wire.These plugs are are used in appliances so that mains electricity can be supplied to appliance safely.
For example,Electric iron-
Here three pin plug is used. The live wire and the neutral wire are connected to the two ends of the heating element whereas the earth wire is connected to the metal body of the electric iron. These three wires are connected to a three pin plug and this plug is connected to a three pin socket. If by chance the live wire touches the metal case of the iron which has been earthed, then the current passes directly to the earth through the earth wire.It does not need our body to pass the current. Therefore we don't get current.
For example,Electric iron-
Here three pin plug is used. The live wire and the neutral wire are connected to the two ends of the heating element whereas the earth wire is connected to the metal body of the electric iron. These three wires are connected to a three pin plug and this plug is connected to a three pin socket. If by chance the live wire touches the metal case of the iron which has been earthed, then the current passes directly to the earth through the earth wire.It does not need our body to pass the current. Therefore we don't get current.