| DESCRIPTION: This model shows a bar magnet and compass sitting on 
                          a table in a classroom at the latitude of Massachusetts. The interaction between 
                          the magnetic field of the bar magnet and the magnetic 
                          field of the earth is illustrated by the fieldlines 
                          that extend out from the bar magnet. Fieldlines that 
                          emerge towards the edges of the magnet generally reconnect 
                          to the magnet near the opposite pole. However, fieldlines 
                          that emerge near the poles tend to wander off and reconnect 
                          to the magnetic field of the earth, which, in this case, 
                          is approximately a constant field coming at 60 degrees 
                          from the horizontal. Looking at the compass, one can see that a compass 
                          needle will always align itself in the direction of 
                          the local field. In this case, the local field is dominated 
                          by the bar magnet. Click and drag the mouse to rotate the scene. Control-click 
                          and drag to zoom in and out.
 
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