What is the process called when a capacitor gains a charge causing a potential difference across its plates?

When a capacitor gains a charge, the process is referred to as charging. This occurs when an external voltage is applied to the capacitor, allowing electrons to accumulate on one plate, creating a negative charge, while the other plate loses electrons and becomes positively charged. This separation of charge results in a potential difference, or voltage, across the plates of the capacitor. This potential difference is directly related to the amount of charge stored and the capacitance of the capacitor, which determines how much charge it can hold at a given voltage.

Charging is a crucial concept in understanding how capacitors function in various electrical circuits, such as smoothing out voltage fluctuations or storing energy for later use. The other answers do not accurately describe this specific process related to capacitors and their behavior under applied voltage.