single PM DC motor?

I took apart a DC motor of questionable quality and I noticed that it uses only one permanent magnet. Basically a round cylinder covering
the whole circumference of the steel can that it sits in. How can this work? I thought you'll need two permanents, one with the polarity N and another S to produce a consistent magnetic field. Can anybody tell me if these motors were designed badly or maybe somebody can educate me on how it can work. Thank you.
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The magnet might be polarized across its diameter. Get a bar magnet and find where the poles are. You might see that it's acting exactly as you'd expect is necessary.
- Owen -

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snipped-for-privacy@yahoo.com wrote:

Hello? All magnets have two poles.
If you found a magnet which was a magnetic monopole, that would be a major breakthrough in physics.
                John Nagle
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