![Figure 3: Some of the lines of B from the small current loop in the centre. The …[Credits : Courtesy of the Department of Physics and Astronomy, Michigan State University]](http://media-2.web.britannica.com/eb-media/53/253-004-FDA5F7F3.gif)
Figure 3: Some of the lines of B from the small current loop in the centre. The current in the loop flows in a clockwise direction when viewed from above.
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