Wiring and componentsQuestion 843 of 1506

After an insulator has broken down, what is true about it?

It always recovers once the voltage is removed.
It becomes a better insulator after the breakdown.
It may no longer insulate, since the breakdown damaged it.
It becomes a magnet.

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Correct answer: It may no longer insulate, since the breakdown damaged it.

Breakdown usually makes a local puncture, so the material may not insulate properly afterward.

Source: Lessons in Electric Circuits I: DC (Kuphaldt), 12.8: Insulator Breakdown Voltage

Questions last reviewed: 18 October 2026

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