The jargon is that strong magnets have a smaller magnetic path. Therefore, the conventional magnets provide a higher suction force than the strong magnets at a long distance. 30CM For a single magnet, either strong or normal, are unable to induce enough suction. Of course, enough magnetic arrangement can achieve this effect.
Conventionally, ferrite or other materials. In fact, powerful magnets compared with ordinary magnets, which is characterized by large table, this factor is about 4 times. Another feature is the high gradient. The gradient represents the change of the magnetic field per unit length. Take the table field to infinity as an example, the faster the magnetic field declines, the higher the gradient. On the contrary, the magnetic field of the strong magnet is more affected by the change of the distance.