也就是说它受合力为零。

That means the force on it must be zero.

youdao

换句话说，合力为零就相当于没有任何力的作用。

In other words zero resultant force is equivalent to no force at all.

youdao

合力为零的话。

But the net force is zero.

youdao

I am going to say if that electron is to stay in its orbit, that is to say it doesn't flee the atom, it doesn't collapse under the nucleus then the sum of the forces on the electron must be zero No net force. And so that will be the sum of a dynamic force plus an electrostatic.

如果电子会保持在它的轨道上运行,既不脱离原子的话，它就不会由于原子核对它的吸引力而被瓦解掉,电子所受的合力一定为零,由于没有合力,所以电子所受力为动态力和静电力的总和。

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