Ferrofluids are colloids - a suspension of superparamagnetic particles in a carrier fluid. If brought into a strong magnetic field, they will form the above pattern of corrugations, an effect known as normal-field instability to physicists, and as wicked cool to everybody else.
In a completely unrelated note, bringing your fingers between two of the above-mentioned neodymium magnets hurts.
Now THAT is FUN (and I don't mean having your finger between two strong magnets).
ReplyDeleteYup. It also stains horribly. Horribly, I say. Especially when your super-strong magnet slips through your fingers and slams into the ferro-fluid :(
ReplyDeleteI remember working in a chemical lab in high school and my boss handing me a quart bottle and a formula for a liter of silver nitrate (bottle was not clearly a quart, by the way). As I'm pouring the silver nitrate into bottle, he says, "Make sure that silver nitrate doesn't get on you. It will stain you for weeks," just as the bottle overflowed and it poured all over me.
ReplyDeleteAh, good times.