Educational Iron Powder with bottle Ideal for Magnetism Studies and Demonstrations

Clear glass bottle: 70x22 mm + 2 pcs. NdFeb magnets D12x4 mm for experiment, +

For ferrofluid visualization: it sounds mystical, but in essence it is “seeing” a magnetic field in the real world using ferrofluid. Briefly and simply What is ferrofluid?

Ferrofluid is a liquid that reacts to magnetic fields, which contains microscopic iron oxide particles floating in water, oil or other medium. When you bring a magnet closer to it, the liquid forms structures of spikes (spikes), which exactly repeat the magnetic field lines.

What does it look like in practice?

When a neodymium magnet is added to a container with ferrofluid:
The liquid forms spikes (vertical “teeth”).
The height of the spikes indicates the strength of the magnetic field.
The shape changes when you move the magnet — you can see the poles, gradient, symmetries.