A magnet is dropped through a plastic tube and subsequently through a 1100-turn coil. The EMF induced is captured by a computer showing the variation of the voltage induced as the magnet falls through the coil.
The graph shows a positive peak corresponding to the magnet approaching the coil and a negative peak corresponding to the magnet leaving the coil.
The negative peak is bigger than the positive peak because the magnet is increasing speed with time as it falls down.
