magmatism

例句：

1. 1. The iron rod was subjected to a strong magnetic field and became magnetized.
   铁棒被置于强磁场中，并被磁化。
2. 2.Magnetic fields are essential for the operation of many electrical devices.
   磁性场是许多电气设备运行所必需的。
3. 3. The scientist discovered that magnets could be used to manipulate objects in space.
   科学家发现磁铁可以用来操纵空间中的对象。