电势能不是能量吗,为什么还有负的什么含义 电势能为什么为负值
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这是一个规定,,就比如你规定在这个地方是零电势能的地方,那么比这个地方高的地方电势能就为正,比这个地方低的地方电势能就为负
Ep=Фq,Ф和q都可以为负,Ep怎么就不可以
势能有正负,无穷远为零势能面
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