magnetic bubble

例句：

1. 1. The magnetized metal piece attracts the iron bar.
   被磁化的金属片吸引铁棒。
2. 2. Magnetic fields can be used to detect hidden objects.
   磁场可以用来探测隐藏的物品。
3. 3. The scientist discovered a new type of magnet that could change the way we think about magnetism.
   科学家发现了一种新的磁铁，改变了我们对磁化的理解。