Spiny Fluids – Ferrofluids and Magnetic Fields
Play! Try running an insulated electrical wire through a thin layer of the fluid and applying an AC current.
The nanoparticles in these solutions are all highly magnetic, so they will align with any magnetic field they come into contact with. The oil substance they are immersed in has low surface tension, so it is able to form long stable spikes along magnetic field lines before turning into a droplet.