So if delta v is negative, in this case delta v is negative, OK, delta v is negative, pressure is a positive number, negative times negative is positive, work is greater than zero.

也就是当活塞,压缩气体的时候，做的功是正的，按照这一规定,我们需要在这里，加上一个负号，这是习惯规定。

麻省理工公开课 - 热力学与动力学课程节选

In this case, V = /P. Have two quantities and the number of moles gives you another property. You don't need to know the volume. All you need to know is the pressure and temperature and the number of moles to get the volume.

以及气体的摩尔数,就可以得到第三个量,知道压强，温度和气体的,摩尔数就可以推导出气体的体积,这称为状态方程,它建立了状态函数之间的联系。

麻省理工公开课 - 热力学与动力学课程节选

5 So similarly would there be the number 65 next to this then the corresponding number for V-I-D and then there's generally a special character at the end that looks like a zero that says end of string here.

同样，A就是,接着再填上V-I-D对应的ASCII码,在最后还有添上一个特殊的字符,有点像0，代表这是该字符串结束。

哈佛公开课 - 计算机科学课程节选

I'm pressing on the gas. So I expect that to be a positive number. The pressure is constant 0 p. The V goes from V1 to zero.

我们对气体加压,所以这应该是一个正数,压强是常数，p，V从V1变成。

麻省理工公开课 - 热力学与动力学课程节选

Path number 1 I'm going straight up in the V-T diagram.

路径1在T-V图上,竖直向上。

麻省理工公开课 - 热力学与动力学课程节选