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From the Q&A

With TJ Byers

Magnetic Measures


I'm confused about Gauss and Oersterds. How are magnetic fields measured? I need this information for a transformer I'm trying to wind.

Les Holmes
via Internet


The units for measuring magnetic fields are Gauss and Oersted. Magnetic flux density is measured in Gauss, while magnetic field intensity is measured in Oersted. The ratio of B, magnetic flux, in Gauss, to H, magnetic field, in Oersted, is defined as permeability, "µ" (pronounced "mew"). The B/H ratio, or "µ," is a measure of the material's properties. It is high for ferromagnetic materials. In air "µ" is equal to one, making Gauss and Oersted identical numerically, adding to the confusion. Still confused? Me, too.