Rare Earth Magnet Basics / Glossary of Magnet Terms / Electrical resistivity
- Electrical resistivity
- Value expressing the difficulty with which electric current flows in the material. The current I in the material is proportional to the applied voltage V (by Ohm's Law) and this coefficient V/I is called the electrical resistance. On the other hand, the specific electric resistance per unit cross sectional area or per unit length is called the electrical resistivity. The larger a material's specific electrical resistance, the more difficultly current flow and the larger the amount of Joule heat generated for the same current flow. For magnetic circuits such as motors with fluctuating magnetic flux amount and direction, the eddy current generated in the magnet is smaller the larger the specific electric resistance.
