As a series of goopy spikes spiral down a bolt in a mesmerizing Youtube video, it almost looks like Mario himself should hop from one to another! But seriously guys, this isn’t an early 1990s video-game, this is some massively-entertaining science!
The Youtube video shows several demonstrations of ferrofluid, a suspension of nano-sized magnetic particles in oil. The magnetic particles are tiny and contained in a surfactant, which helps keep the particles evenly distributed throughout the liquid.
In the video, an electromagnet under the bolt provides the magnetic field. And as the liquid aligns itself with the invisible pull of the magnet, surface tension holds the fluid together. Meanwhile, gravity forces the liquid down the screw, resulting in the downward motion of the spikes.
Check it out from Live Science:
The shape “is a minimum-energy solution between the gravitational energy, the surface tension energy and the magnetic energy,” meaning the substance chooses the route that demands the least amount of energy, Jackson told Live Science.
In some [videos], the demonstrator holds additional magnets, which can alter the shape of the ferrofluid further, or move it around a surface like a snuffling hedgehog.
NASA scientists invented ferrofluids in the 1960s when they were trying to figure out how to efficiently move rocket fuel from a tank into an engine in a zero-gravity environment. The researchers thought that by magnetizing the fuel with tiny iron oxide particles, they might be able to use a magnetic field to suck the fuel into the engine, leaving behind any pesky gas bubbles that could cause damage, according to NASA’s Technology Transfer Program.
Solid-rocket propellants obviated the need for the ferrofluids in space, but scientists quickly realized that ferrofluids could also be used to form seals to protect semiconductor chips during fabrication. Probably the most common industrial application today is in speakers, Jackson said. Ferrofluids are used to dampen vibrations in speaker components to prevent a distorted sound.
Jackson and his colleagues have a different use for ferrofluids in mind. They’re studying ferrofluids as self-assembling thrusters on tiny satellites. Traditional propulsion systems work well on large satellites, Jackson said, but an increasing number of the satellites shot into orbit are the size of cellphones or shoe boxes. Many use electrospray thrusters, which use tiny electrified needles to spray jets of fluid in order to propel the satellite. But the spiky hedgehog shape that ferrofluids form under the influence of a magnetic field can also shoot jets of ions — a form of propulsion that requires only a magnet, not a precision-fabricated needle.
Check out the amazing video!
Can you think of another application
for this amazing magnetic fluid?