Miscellaneous
Paper clips in the magnetic field of electric motors:

Sokolov's book about the first stage of the Leningrad metro, 1957.
And in general, what does not happen in the Saint-Petersburg metro ;)
Paper clips in the magnetic field of electric motors:
Sokolov's book about the first stage of the Leningrad metro, 1957.
And in general, what does not happen in the Saint-Petersburg metro ;)