Where's the North Pole?

We know the bar of magnets have south and north pole at two ends of the bar. I wonder where is the south and north poles if we make magnets be sphere.
- jason (age 23)
IL

The poles are aligned along the direction of the original magnetizing field.  There are several ways of finding them:   You could use a small bar magnet and find out where on the sphere its South Pole is attracted.  You could sprinkle a few iron filings on it and find out where tend to accumulate.  However with this method you don't know which of the two accumulated bunches is North.

LeeH

(published on 02/16/2010)