I was first just reading about how MRIs have got really big magnets in them, and thinking: I know that the magnetic field extends out away from them. It can’t extend out forever, because when I drop my keys, they don’t go flying off to the nearest MRI.
So the first question is: How far out does that magnetic field go? That I could figure out by looking at MRI manuals. I was reading through these guides, and they were like: “If you have this kind of equipment, you need to put it this far away. And if you have this kind of equipment, it needs to be this far
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