1. When current flows through a metallic conductor, the free electrons in the metal start moving from the end which is at the lower potential.
2. These moving free electrons collide with the atoms of the metal.
3. At each collision, a part of kinetic energy of electron converts into heat.
2. These moving free electrons collide with the atoms of the metal.
3. At each collision, a part of kinetic energy of electron converts into heat.
