Design and technology as well as science teachers are buying the amazing ferrofluid – a truly magnetic liquid. This consists of micron size magnetic particles (magnetite) in a mineral oil. Particles are coated in a surfactant which prevents them clumping together.
When a magnet is in close proximity the magnetic particles in the Ferrofluid take up the shape of the magnetic field – a 3-D version of the classic iron fillings on a piece of paper experiment that we used to do in schools.
See an amazing use of Ferrofluid in the video below…
The apparent density of ferrofluid can be changed by applying a magnetic field. E.g., place a one pence piece in a shallow dish (5mm) of ferrofluid and it will sink. Bring a powerful magnet underneath and the coin will float!
Supplied in a plastic jar containing 10ml of Ferrofluid. A rare earth magnet is also supplied.
Requires scissors, sticky tape and pliers (or similar).