What is equal to

And we know what that's equal to, this is something we've been over and over, ionization energy is simply equal to the negative of the binding energy.

而且你知道它等于什么，这是我们说过一遍又一遍的，电离能就等于，负的束缚能。

And it should make sense where we got this from, because we know that the binding energy, if we're talking about a hydrogen atom, what is the binding energy equal to?

很容易理解，我们怎么得到这个的，因为我们知道，结合能，如果，对氢原子来说，结合能等于什么？

And it says that the divergence of the electric field is equal to, so this is a just a physical constant, and what it is equal to depends on what units you are using.

它说的是，电场的散度等于，这是一个物理常数，它等于什么，是基于所用的单位。