Magnetism and electromagnetismQuestion 203 of 1506

The current in an electromagnet is doubled, and at the same time its number of turns is cut in half. What happens to the magnetomotive force?

It is cut in half
It doubles
It stays the same
It becomes four times larger

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Correct answer: It stays the same

mmf is current times turns. Twice the current with half the turns gives the same product.

Source: Lessons in Electric Circuits I: DC (Kuphaldt), 14.2: Electromagnetism

Questions last reviewed: 18 October 2026

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