Ferrofluid
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Ferrofluid is a great invention. It is made from small ferromagnetic particles encased in oil. A magnetic liquid! When in the presence of a magnetic field it produces some great looking and sometimes unexpected effects.
The only downside is that is is somewhat expensive, and stains EVERYTHING permanently if not cleaned up quickly. If you think keeping iron filings off your magnets when playing around is tough, this stuff is far harder. It is almost alive, in that if you have a magnet near a container it can send a pseudopod OVER the top and flow all over the magnet and your fingers like an amoeba. Kind of creepy! :-)
You can get it from
Educational Innovations
which has a great display vial of it.
WonderMagnets sells 50ml bottles of the stuff.
This is a small bottle of Ferrofluid. You can see it defying gravity as I
hold it under a stack of magnets.
The brown tint to the glass is due to the staining of the oil.
If you place the bottle on a STRONG magnet it will eventually pull the
stain mostly off the glass, but often some spots will stay and you always
have a faint stain left.
Here I have a pair of 1/2" cube magnets on either side of the jar. Just like filings, but with much better details.
Underneath the plastic tray is a Halbach Array in various positions. This makes for some neat looking fields.
This was a failed attempt to coat a Diamagnetic Floating magnet in Ferrofluid.
Numerous problems with this. The first being if the oil gets on the bottom it will stick to the surface and no longer float.
Another is that if you get ANY ferrofluid on the surface of the levitation device or the graphite it will interfere and you will need to replace those parts. Here I used plastic wrap to coat the expensive bit of graphite.
The final problem is I just can't float a magnet high enough to get enough fluid around it to show anything interesting. Have to wait for the next generation of supermagnets.
Some neat patterns here in the thin film of Ferrofluid on the bottom of the tray here. 1/2" magnets are on each side of the tray.
The other tray has some small ring magnets in a 2x3 array.
Each field below is produced by a pair of 1/2" magnets.
&nsbp; They are stuck together in three diffrent ways.
Can you tell which is which?
