@article{oai:iwate-u.repo.nii.ac.jp:00012549,
 author = {Sasaki, Shuichi and Yagi, Ichimasa and Murakami, Masato},
 issue = {4},
 journal = {Journal of Applied Physics},
 month = {Jan},
 note = {An iron ball floats in midair in a plastic box when several iron balls were attracted by a permanent
magnet. A complex interaction between magnetized sphere materials and a lifting magnet enabled
the suspension of an iron ball. The balls in the first row are simply attracted by the lifting magnet.
The ball in the second row is also attracted by the lifting magnet, however, due to the repulsive
forces exerted from the balls sitting above, it can float in midair. We also found that there are two
stable positions for the ball to float. The floating ball could be transported from one equilibrium
position to another by simply rotating the lifting magnet. This will make it possible to construct a
noncontact load transport device.},
 pages = {2090--2093},
 title = {Levitation of an iron ball in midair without active control},
 volume = {95},
 year = {2004}
}