Electrical mathQuestion 836 of 1506

For a custom busbar cut from metal stock, where only length, width and height are known, which unit of specific resistance is usually the most convenient?

Ohm per amp
Ohm-metre or ohm-centimetre
Ohm-circular-mil per foot only
Siemens per volt

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Correct answer: Ohm-metre or ohm-centimetre

With rectangular dimensions you can find the area directly in square metres or square centimetres, so a metric specific resistance fits.

Source: Lessons in Electric Circuits I: DC (Kuphaldt), 12.5: Specific Resistance

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Questions last reviewed: 18 October 2026

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