Electrical mathQuestion 801 of 1506

Why was the circular mil unit created?

To measure wire length
To measure wire weight
To measure wire resistance in ohms per metre of length
To remove the need for π and the radius when finding wire area

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Correct answer: To remove the need for π and the radius when finding wire area

The unit is sized for circles so the formula is simple.

Source: Lessons in Electric Circuits I: DC (Kuphaldt), 12.2: Conductor Size

Questions last reviewed: 18 October 2026

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