您說的對！標量有正負數值，而矢量是有正負關係，意義完全不同。我想我們這裏討論的正能量講的是正負關係吧？

來源: 平等性於 2020-12-15 09:44:41 [博客] [舊帖] [給我悄悄話] 本文已被閱讀：次

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