Hi
I’m not an expert in magnet. The magnet are called so that the material that forms it becomes superconducting. While becoming superconducting, you can create much stronger magnetic field than the usual magnets. So if you need very strong magnet, this is what you go for. On property of superconducting material is that you can’t have magnetic field inside it. So if you bring in a permanent magnet (like a fridge magnet) on superconducting material, it would repel it, and therefore makes it levitate!
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