The external energy is imparted to which particles that flow in a conductor?

In electrical conductivity, it is electrons that carry the external energy imparted to particles flowing through a conductor. In metallic conductors, atoms are arranged in a lattice structure, where the outermost electrons are loosely bound and can move freely. When an external voltage or electric field is applied, these free electrons gain energy and drift towards the positive end of the conductor, creating an electric current.

This movement of electrons is facilitated by the conductive material's properties, which allow electrons to move more freely compared to protons, neutrons, or ions. Protons are bound within the nucleus and do not move freely in the conductor. Neutrons, being neutral and also part of the atomic nucleus, do not participate in electrical conduction. Ions, while they can conduct electricity in solution or plasma, are not typically the primary carriers of current in metallic conductors. Thus, the role of the electrons is crucial in the process of conducting electricity.