Ferrofluid Defies Physics
This is WAY cool! I haven't blogged for a while, but I just had to share this! Ferrofluid is a liquid that becomes polarised in the presence of a magnetic field. Here's the technical definition, straight from Wikipedia: "Ferrofluids are composed of nanoscale ferromagnetic particles suspended in a carrier fluid, usually an organic solvent or water. The particles are coated with a surfactant to prevent their agglomeration. Although the name may suggest otherwise, ferrofluids do not display ferromagnetism, since they do not retain magnetization in the absence of an externally applied field. In fact, ferrofluids display (bulk-scale) paramagnetism, and are often referred to as being "superparamagnetic" due to their large magnetic susceptibility."
A bunch of scientific mumbo-jumbo to me, I'm afraid, but the behaviour of the fluid is fascinating to watch. This YouTube clip is wonderfully entertaining and demonstrates the fluid's seemingly impossible properties. There are lots of examples on YouTube, accompanied — not surprisingly — by abundant debate re whether or not it's CGI fakery. There's even a television commercial using the fluid.
Kinda reminds me of those 50's Wooly Willy toys we had as kids, with a goofy-looking guy and iron filings you dragged around with a magnet, to give him hair and a beard.
Ain't the web grand?! Every now and then, one tends to forget the incredible marvels this technology has brought to our desktops.