Magnetism and electromagnetismQuestion 890 of 1506

Which change increases the inductance of a coil, with everything else equal?

Using fewer turns of wire
Making the coil much longer
Using more turns of wire
Replacing an iron core with air

Show answer

Correct answer: Using more turns of wire

More turns give more magnetic force for the same current, so inductance is greater.

Source: Lessons in Electric Circuits I: DC (Kuphaldt), 15.3: Factors Affecting Inductance

Questions last reviewed: 18 October 2026

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