With each passing infinitesimal time interval another infinitesimal layer is added to the region within which the magnetic field exists.

随着每一个无限小的时间间隔另一个微层被添加到一个区域内，磁场就存在于这个区域内。

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With each passing infinitesimal time interval another infinitesimal layer is added to the region within which the magnetic field exists.

随着每一个无限小的时间间隔另一个微层被添加到一个区域内，磁场就存在于这个区域内。

youdao