When mixing or agitating delicate solutions in the chemistry lab, a magnetic stirrer is often the ... The build consists of a 3D printed base, containing a simple brushed motor.

The needle will turn and then come to a complete stop. It will be facing magnetic north. You can check this by placing the compass next to the bowl. The needle is being affected by the Earth’s ...

Until the arrival of GPS, the magnetic compass was the single most useful navigational tool available to humans. But it’s a recent invention. Although Chinese explorers understood the principles of ...