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Question
is there any thin like nine-pole magnet ?
How does multiple pole magnet exits?
Hello,
multipole magnets are just arrangements of normal two-pole magnets made to produce a defined field in 3D space. Hence nine-pole magnet does not exist.
The names or multipoles come from electrostatics, where you deal with multiple charges (several + and other -) arranged in space in a certain way. these 'clouds' are NOT called multipoles, it's the mathematics that makes this problem easier to tackle, which produces a series of terms field=t1+t2+t3+t4+... where t's are in different powers of your distance from the cloud. These t's are calles 'monopole term', 'dipole term', 'quadrupole term','octupole term', etc. I can write you more, but for that I would need to know, what level in physics you are.
A similar expansion series can be produced, when you deal with arrangements of magnets. They start as 'dipoles', so the magnetic monopole term will be always zero. Also, for a different reason, you only get '-poles' in powers of 2: 2, 4, 8, 16,... That is pretty much reflected in the constructions of multipole magnets, you get them also in the same 'power-of-2' arrangements.
I hope this answers your question.
Take care,
Daniel
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Daniel Mazur
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