What defines a complete electric circuit?

A complete electric circuit is defined as a path that allows electric current to flow continuously. This path must include both positive and negative currents because electricity involves the movement of electrical charges, which can be either positive (protons) or negative (electrons).

In most practical applications, electricity is generated and transmitted as a result of the flow of electrons, which are negatively charged particles. However, the concept of current in a circuit can be understood as consisting of both the movement of electrons (negative current) and the conventional current flow which is considered to be from positive to negative. Therefore, for the circuit to function correctly and enable devices to operate, both types of charges must be involved in creating a complete loop.

Static electricity, which does not represent a continuous flow of electric charge, cannot constitute a circuit, as it requires a closed loop for current to flow. A path consisting solely of one type of current, whether positive or negative, also fails to form a complete circuit because it does not allow for the necessary balance and return path that a complete circuit requires. Thus, the presence of both negative and positive currents is what truly defines a complete electric circuit.