Magnetism and electromagnetismQuestion 200 of 1506

The same total flux passes through a core section. The cross-section area of that section is cut in half. What happens to the flux density?

It becomes zero
It is cut in half
It does not change
It doubles

Show answer

Correct answer: It doubles

Flux density is total flux divided by area. The same flux in half the area gives twice the density.

Source: Lessons in Electric Circuits I: DC (Kuphaldt), 14.4: Permeability and Saturation

Questions last reviewed: 18 October 2026

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