Feb 6, 2007 4
Experiments in electromagnetic induction
Our first working test setup visualised electromagnetic induction by changing the intensity of a LED. We routed the +5V power through a potentiometer into a wire coil and from there the to the analog input pin of the Arduino NG. The changes in the magnetic field inside and around the coil(like when waving a magnet near the coil) induce small voltages in the coil which show up in the readout of the analog pin.
Minimum and maximum voltage values and the difference between these are computed for 100ms intervals. The difference is used as a measure of the amount of voltage fluctuation and translated into the intensity of the LED.
— Jan & Miska