Magnetism and electromagnetismQuestion 891 of 1506

A coil is stretched to twice its length, with the same turns and core. What happens to its inductance?

It decreases.
It increases.
It stays the same.
It doubles exactly.

Show answer

Correct answer: It decreases.

A longer flux path means more opposition for the same ampere-turns.

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

Questions last reviewed: 18 October 2026

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