The action of the negative pole of a magnetic needle is just as real as the action of the positive pole.
一根磁针的磁极作用，无论正负都是一样的真实。
The action of the negative pole of a magnetic needle is just as real as the action of the positive pole. To decline is to accept — the other alternative.
一根磁针阴极的作用和阳极的作用都是一相真实的；拒绝也是一种接受——这些都是二中择一的选择。
The action of the negative pole of a magnetic needle is just as real as the action of the positive pole .
这个效应表明，有一种垂直于圈平面的力作用在磁极上。
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