Induction - Lenz's Law Apparatus

To use the Lenz's law apparatus a magnet is dropped down a tube made of a material that is certainly not magnetic. I tried sticking a magnet to it, but the magnet just fell off. On the bright side, one of the pieces of the shattered magnet was now small enough to fit in the tube.

And that is just what I did:


 Note: this dashingly handsome physicist not necessarily included with your experience with the Lenz's law apparatus.

The timer was started simultaneously with dropping the magnet (very hard to show clearly via picture, so take my word on this!). Then we wait...and wait...and wait...until, finally:

That was a very slow fall. If you ever find yourself free falling through the air without a parachute, try to act magnetic and aim for a large conducting tube to slow your descent.

What happens here is that, as the magnet falls, the changing magnetic fields throughout the conducting tube creates currents opposite to the change as seen by the tube. These currents create an upwards force that acts upon the falling magnet, greatly slowing its rate of descent.

There are a few other flavors of this demonstration, as shown below. Inside the slotted tubed are two plugs: one magnetic plug and one nonmagnetic. The nonmagnetic plug falls normally while the magnetic plug falls slowly.