and so when the motor spins, the stirrer spins in the solution, with no physical contact required. It’s a simple way to build a magnetic stirrer at home without having to shell out big money for ...

You’ll also see how this DIY motor powers various Lego contraptions. Finally, we’ll connect it to a power supply and push it to its limits to explore how it performs under maximum load.

Bragging rights are not exactly what [Jeremy Fielding] has in mind for his DIY dynamometer ... calculate the power output of a motor: speed and torque. A magnetic tachometer does the job of ...