By chance(playing around really) I saw that a spring(mainly from a pen) placed on a neodymium hard-disk magnet(and then flicked by your finger at the top) makes a nice-effect (see youtube video ). It appears to oscillate in slow-motion(looks like tornado).
Of course, "slow-motion" is purposely simplistic and unscientific – I am very far from a physicist.
Here's the video – http://www.youtube.com/watch?v=n0OJQ1iXZg0&feature=channel_video_title
I was too impatient in the video though, I should have zoomed in on the spring and waited. Sorry about that..
Here's a page about the magnets used:
http://www.reuk.co.uk/Hard-Disk-Drive-Magnets-For-Wind-Turbines.htm
Here are the polarities, plus a horizontal profile below:
More details: You really want to use a retractable pen spring, the thin kind. And Hard-drive magnets are key – I think it doesn't work with others. I think it's partly because of the 4-poles of a neodymium magnet. i.e, it's actually two-magnets-in-one.
Cigarette lighters also have a long delicate magnet, which is good but too tipsy.
LBNL, supposedly you can stack these magnets, but they seem impossible to separate from the backing-piece. I appreciate any tips or advice.
Best Answer
First of all, I am not an expert on magnetism, so this is more of an additional question than answer (cannot add pictures to comments, so thats why its here).
In the case of ferrous materials they generate an magnetic field inside material (ok?).
Opposite signs attract each other (right?).
the position of the spring happens to be the local minimum of potential energy by symmetry principle (or you can actually calculate this).
all the other phenomena are just corrections to above phenomena (?).
If all above are summed together, the spring is just oscillating around a local potential energy minimum, because of the magnetic field, not because of the spring properties. This is also why the coin oscillates the same way.
Anyway could you comment on this, I would like to know where I went wrong (if anywhere).