One amp of current flows through a wire when one ___ flows past a point in one second.

• A. Coulomb
• B. Ohm
• C. Volt
• D. Electron

Answer: (A)

One ampere (or amp) of current is defined as the flow of one coulomb of charge past a point in one second. This is grounded in the fundamental definition of electric current, where current is the rate of flow of electric charge. A coulomb is the unit of electric charge, and it quantifies the amount of charge that can flow when an electric potential causes a current to move through a circuit.

In this context, the other terms do not refer to the flow of charge in the same manner. An ohm is a unit of resistance, measuring how strongly a material opposes the flow of electrical current. A volt is a unit of electric potential, which represents the potential energy per unit charge. An electron is a subatomic particle that carries a small charge, but the flow of electrons themselves doesn’t define the quantity of current without considering the total charge they represent.

Thus, stating that one amp of current flows when one coulomb passes a point in one second is the precise definition consistent with the principles of electricity and measured in standard units.