du We can talk about du for the system well, w that's q plus w.

我们可以讨论它的，等于q加。

麻省理工公开课 - 热力学与动力学课程节选

U And then if we can also determine delta u, then we know this, we know delta u is q plus w w, then we can determine work as well, right?

然后，如果我们也能定出△,然后我们知道这个,我们知道△U等于q加？

麻省理工公开课 - 热力学与动力学课程节选

And because there is an explicit relationship between u, delta u, q and w, you can always find the easy way to derive the change in internal energy or the heat or the work.

因为Δu，q和w之间,有明确的关系，一般来说,内能或热或功的变化,易于计算。

麻省理工公开课 - 热力学与动力学课程节选