Magnetic stirrer

A magnetic stirrer consists of a small bar magnet and a stand or plate containing an electromagnet. The bar magnet is placed in a vessel containing a liquid to be stirred, and the vessel is set on top of the stand, where a rapidly oscillating magnetic field causes the bar magnet to spin at high speed.

Magnetic stirrers are sometimes preferred to gear-driven motorized stirrers in chemical research because they are quieter, more efficient, and have no moving parts to break or wear out (other than the simple bar magnet itself).