Current will only flow when what is applied as an electrical force?

• A. Current
• B. Voltage
• C. Capacitance
• D. Resistance

Answer: (B)

Current flows only when there is a driving electrical force pushing the charges, and that force is voltage—the potential difference across the circuit. When voltage is applied, an electric field is created that pushes charges through the conductor, producing current. The amount of current depends on how strong that push is relative to any opposition, described by I = V/R: more voltage (with the same resistance) means more current. Capacitance stores charge and can affect how current changes over time, but it doesn’t provide the continuous push by itself. Resistance opposes the flow, reducing current for a given voltage. So applying voltage is what makes current flow.