Chapter 10. Electricity and Magnetism
Hall sensors detect a magnetic field. They come in different varieties: some just detect the presence of a magnet, while others can tell you the strength of the magnetic field in teslas.
Voltage and current sensors work like a multimeter, measuring electricity passing through them. They can easily measure power that would otherwise break a microcontroller’s analog input pin.
An electronic compass can tell you where magnetic north is. Better ones combine an accelerometer, so that ...