An electric current is defined as the flow of what through an electrical conductor?

An electric current is defined as the flow of electrons through an electrical conductor. In conductive materials, particularly metals, atoms have free electrons that can move easily across the material. When a potential difference is applied, these free electrons move, creating an electric current.

Electrons are negatively charged particles, and their movement constitutes the flow of electricity in an electrical circuit. The understanding of electric current as the flow of electrons is fundamental in both physics and practical applications, such as electronics and electrical engineering.

Other particles like protons and neutrons do not contribute to electric current as protons are bound within the nucleus of an atom and are not free to move, while neutrons are neutral and do not carry any charge. Ions, while they can carry charge and contribute to current in certain contexts like electrolysis or in ionic solutions, do not represent the conventional definition of electric current in metallic conductors.