Question: How strong is the strongest magnet? How much damage could it do?

Giuditta Perversi answered on 12 Nov 2015:

The strongest magnet that are currently around are electromagnets with superconducting wires!
In less boosting terms, the way you create the magnetism is by passing electricity through a wire (electricity and magnetism are really strongly correlated!). The issue with most wires is that they tend to resist a bit to electricity when it passes by, and you lose energy; a superconducting wire needs to be cooled at something like – 200°C, but at that point it can conduct electricity without any resistance!
The electromagnet that you create with this technique is around 400,000 times stronger than the Earth’s magnetic field! (I think they broke the record in 2011 with one 500.000)
They are even more common that you can think, every hospital with a Magnetic resonance (MRI) has one!

If you were thinking about a magnet like the one on your fridge but much strongest, they are called permanent magnet, instead!
They are little disk of material with strong magnetic properties, the best one is a compound with Neodymium, Iron and Boron (Nd2Fe14B), but it’s 10 times weaker than an electromagnet! (still a good 20,000 times stronger than the Earth’s magnetic field when you are in range 😉 )

It’s not yet clear if being constantly exposed to magnetic fields as strong as these ones can give you damage as a human being, it’s possible that it doesn’t.
On the other hand, if you use an electromagnet you need to keep a safety distance because if you have anything metallic or the like on you it will try to stick to the magnet AT ALL COST, meaning that if you have something metallic in your mouth it will pierce your skull like a bullet to get to stick to the magnet (that’s the reason they put titanium in the prothesis, it doesn’t react to magnetic fields!)