Question

in an electric circuit why does the wire, switches, bulb or devices become hot when the switches turn on the current flows through it

Answer 1

Dear student,

The heat generation takes place in any electric circuit due to the resistance of different material of wires, switches, bulb, or devices.

Ex.
An electric iron contains coils of high resistance wire made of nichrome alloy. When iron is connected to the power supply by insulated copper wires then a large amount of heat is produced (due to the high resistance), but a negligible heat is produced in the connecting wires of copper because copper has very very low resistance. So it remains cold.

Regards