permanent bipolar magnet

• 双极永久磁铁

permanent bipolar magnet的用法和样例：

例句

1. A permanent magnet assists closing and latches the breaker in the closed position.
   一个永久磁铁帮助跳开关闭合并锁定在闭合位。
2. Other objects become magnetic only when in a magnetic field caused by a permanent magnet or an electromagnet.
   其它物体只有在处于永久磁铁或电磁铁形成的磁场中时才具有磁性。