If there were no voltage on the plates, we would expect everything to be over here in some negative value falling.

如果板子上没有速度，这些可能都在这,都是负值下降的。

麻省理工公开课 - 固态化学导论课程节选

And I am able to vary the voltage on the plates making this for argument's sake negative and this for argument's sake positive.

我可以改变两个板子上的电压,为了论证，这个是负电,这个是正电。

麻省理工公开课 - 固态化学导论课程节选