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This is magnetic patty, a non-newtonian fluid embedded with filings of
iron or steel.
Its name may be a misnomer;
by itself it's not magnetic, but because of it's ferromagnetic flecks
it will adhere TO a magnet with ease.
Because its fluid-like nature, it can provide insight into magnetics.
Here, I'm using a very powerful neodymium magnet, from computer hard drive, to draw
the magnetic flecks into alignment with the rare earth magnet's magnetic field.
The force is so strong
that it shapes the putty, in real-time, allowing us to see the forces
acting on the putty, compared to the force of gravity alone acting on the
blob behind.
While the putty is not by itself naturally magnetic
it is a fantastic analogue to understanding how to make
a magnet.
While a ferromagnetic material, such as iron, steel, or
neodymium iron boron, is in a semi-solid state,
it is exposed to a powerful magnetic field, often from an electromagnet.
The internal magnetic dipoles align with the applied field,
all the 'norths' facing one direction, and the 'souths' facing another
Remove the applied magnetic field
and the new solid retains its magnetic properties.
But, randomize the orientation of the dipoles again,
and the material's ingrained magnetism is lost.
For Tech Laboratories, I'm Tech Adams,
saying: Keep Thinking, and thanks for watching.