When a capacitor is fully charged, there is what?

When a capacitor is fully charged, there is what?

• A. Current
• B. Capacitance
• C. Potential difference
• D. Resistance

Answer: (C)

In a DC circuit, when a capacitor becomes fully charged, a steady potential difference appears across its plates. The charging stops because the voltage across the capacitor matches the supply, so no net current flows through the capacitor in the steady state. The stored charge and voltage are related by Q = C × V, so the maximum charge on the plates corresponds to the maximum voltage across them. Capacitance is a property of the device and does not indicate the presence of a voltage by itself, and resistance isn’t the meaningful descriptor for an ideal capacitor in steady-state DC (the current through an ideal capacitor is zero once fully charged).

In a DC circuit, when a capacitor becomes fully charged, a steady potential difference appears across its plates. The charging stops because the voltage across the capacitor matches the supply, so no net current flows through the capacitor in the steady state. The stored charge and voltage are related by Q = C × V, so the maximum charge on the plates corresponds to the maximum voltage across them. Capacitance is a property of the device and does not indicate the presence of a voltage by itself, and resistance isn’t the meaningful descriptor for an ideal capacitor in steady-state DC (the current through an ideal capacitor is zero once fully charged).