If you were to tell a child playing with a horseshoe magnet and pieces of iron that his uncle has a much bigger magnet that can lift everything and everybody, the child would probably believe you and might even ask for a ride on the magnet. If a physicist were present at such a conversation, he or she—armed with knowledge and experience—would probably smile condescendingly. The physicist would know well that only a very few materials—such as iron or nickel—are strongly magnetic, while the rest of the world's materials are not; to be precise, the rest of the world is a billion times less magnetic. This number seems obviously too large to allow common substances (water, for example) to be lifted even by the most powerful magnets; a billionfold increase in magnetic fields can be found only on neutron stars. In this case, however, knowledge and experience would mislead the physicist: In fact, all materials can be lifted by using magnetic fields that are rather standard these days. In principle, even a child can be levitated by a magnet, as we shall see below.
Everyone's Magnetism: Though it seems counterintuitive, today's research magnets can easily levitate seemingly nonmagnetic objects, thereby opening an Earthbound door to microgravity conditions.
Andrey Geim; Everyone's Magnetism: Though it seems counterintuitive, today's research magnets can easily levitate seemingly nonmagnetic objects, thereby opening an Earthbound door to microgravity conditions.. Physics Today 1 September 1998; 51 (9): 36–39. https://doi.org/10.1063/1.882437
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