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Q & A: magnetic suspension

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Most recent answer: 11/10/2013
Q:
Is it possible to suspend a neodymium magnet between two electromagnets and if so can you point me to suitable information that will help me with my eperiment
- Ken (age 18)
Ireland
A:

If the electromagnets are run with fixed current and magnetic field, then no. Earnshaw's theorem says that there is no stable configuration for anything like that. It's possible that with some fancy active feedback device controlling the currents through each of the coils on the electromagnet you could suspend the magnet. You might search under "maglev" for guidance on how magnetic suspension systems for trains work. Considering only the conventional systems- the ones using superconductors evade the conditions for Earnshaw's therem to apply and thus do not require active feedback.

Aha, perhaps this article would be a good place to start: .

Mike W.


(published on 11/10/2013)

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