How does this “simple” electric train work?

up vote 51 down vote favorite 22

In this YouTube video, a dry cell battery, a wound copper wire and a few magnets (see image below) are being used to create what can be described as "train". It looks fascinating but how does this experiment work? Update 8th August 2016: This problem has been completely worked out in a paper that was published in the January 2016 issue of American Journal of Physics. Link: Am. J. Phys. 84, 21 (2016); http://dx.doi.org/10.1119/1.4933295 electromagnetism classical-electrodynamics shareciteimprove this question edited Aug 8 '16 at 10:32 asked Dec 2 '14 at 16:35 noir1993 91611027

This is some sort of Homopolar motor. Search Youtube for this term, there are a lot of funny experiments with wires and magnets. – Dims Dec 2 '14 at 21:36 wow. i created an account to ask this ;) – naveen Feb 8 '15 at 3:31 If I had asked it, I would have required someone to do it themselves to verify that it worked. The USPTO has given patents on warp drive and time machines based on theory. – EngrStudent Feb 8 '15 at 23:41