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磁通量变化量一定为正吗

更新时间: 2020-07-13 00:00:00     

磁通量的变化量的大小一定是正值,这句话是不正确的。首先,磁通量也是有方向的,一般穿进为正,穿出为负。如果规定了正方向以后,磁通量的变化量如果是正值,说明磁通量在变大,如果磁通量的变化量为负值,说明磁通量在减小。

关键词: 磁通量 变化 一定

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