Ways To Empirically Identify a Magnet’s Polarity

Every magnet has a north and a south pole, but which is which. Sometimes it matters. If a product one builds features a magnetic closure or other part, the polarity ….

Ways To Empirically Identify a Magnet’s Polarity. So how does one ensure they never glue a magnet wrong again. [Clough42] shows several ways to identify a magnet’s north and south poles using things many of us probably have ready at hand, and goes into a bit of theory while he’s at it.

Probably the easiest way is to use a known-good and clearly labeled reference magnet. But if that’s not available, a simple magnetic compass can help. Because opposite poles attract, a compass’s north point will be attracted toward a magnet’s south pole, and vice versa.

A Hall effect sensor, or an electromagnet — the winding and current flow determine the polarity — are other ways to measure a magnet’s poles.