Safety and work practicesQuestion 850 of 1506

A capacitor is disconnected from its supply. What should you expect about its stored voltage?

It falls to zero the moment it is disconnected.
It reverses polarity as soon as it is disconnected.
It may stay charged a long time, leaking away slowly.
It cannot hold any voltage without a supply connected.

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Correct answer: It may stay charged a long time, leaking away slowly.

A capacitor tends to stay charged. Only internal leakage slowly drains it, which can take years for some types.

Source: Lessons in Electric Circuits I: DC (Kuphaldt), 13.1: Electric Fields and Capacitance

Questions last reviewed: 18 October 2026

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