And the reason is, and this will come up on the problems and a lot of students end up using this equation, which is why I want to head it off and mention it ahead of time, we can't use an equation because this equation is very specific for light.

原因是，很多同学在解题时,都会用这个方程，所以我要,事先提醒你们一下,我们不能用这个方程，因为它只对光是用。

麻省理工公开课 - 化学原理课程节选

so much understanding of how skin responds to light, how hair moves,

对皮肤对光的反应、头发的摇动，有很多的理解，

没有特效的话 - SpeakingMax英语口语达人

c We know it's very specific for light because in this equation is c, the speed of light. So any time you go to use this equation, if you're trying to use it for an electron, just ask yourself first, does an electron travel at the speed of light?

我们知道它只对光适用是因为在这个方程里有,光速，所以下次你们用这个方程前，如果你们要把它用到一个电子上，先问问你自己，电子的运动速度是光速吗？

麻省理工公开课 - 化学原理课程节选