Charge storage concept: is a capacitor considered “charged” when one plate holds an excess of electrons while the opposite plate holds an equal deficit, producing an electric field between them?

Introduction / Context:Capacitors store energy via separated charge on two conductors. Clarifying what “charged” means helps avoid confusion between net device charge and equal/opposite charges on the plates that create voltage.

Given Data / Assumptions:

• Two conductive plates separated by a dielectric.
• External source applies a potential difference V.
• Ideal leakage (very high resistance) during the charging interval.

Concept / Approach:When a voltage is applied, electrons accumulate on one plate (negative), while electrons are removed from the opposite plate (positive). The charges are equal in magnitude and opposite in sign, producing an electric field in the dielectric. This condition is precisely what we call a “charged capacitor,” whether the source is DC or an instantaneous AC value at a moment in time.

Step-by-Step Solution:

Verification / Alternative check:Disconnecting the source leaves the charge separation and voltage (subject to leakage), confirming stored energy without continuous current.

Why Other Options Are Wrong:Electrolytic/DC/air qualifiers are unnecessary: the definition applies to all capacitors, all dielectrics, and both DC and instantaneous AC states.

Common Pitfalls:Thinking a “charged capacitor” must have net device charge; in reality, the net is near zero while plates have equal and opposite charges.

Final Answer:Correct