However, the speed of the rotor rotation speed did not change the high magnetic field, or magnetic line of force will not be able to cut the copper.

不过此转子转动速度没有磁场变换之速度高，否则磁力线将不能为铜棒所切割。

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Place any magnet under the unit and set it on an overhead projector-and you will see the filings moving to line up along the lines of magnetic force.

将一磁铁放在盒下并将它放在一投影机下面——你即可看到铁粉随著磁力线的分布而移动。

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The rotation will last for ever if the permanent magnetic ring and the magnetic force line of the permanent magnet SN exist for ever.

只要永磁环和永磁体sn的磁力线永久存在，旋转也将始终存在。

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