But you don't compress it so quickly that you're not in there reversible process so you compress that if you were to feel the temperature of the air and you can feel it through the nozzle gives you an idea of the temperature of the air inside your bicycle pump.

但是压缩速度,也不能太快,否则就不是,可逆过程了,这样当压缩气体时,从喷嘴可以感受到,内部气体的温度。

麻省理工公开课 - 热力学与动力学课程节选

This is real, unlike the Joule coefficient which is very small so that most gases have tiny Joule coefficients. So if you do a Joule experiment, you hardly measure a temperature change. With real gases, here you do actually measure it. You can feel it with your finger on your bicycle tire.

系数那样小以至于,大多数气体的焦耳系数,都很小，所以如果你做焦耳实验,很难测量出温度的变化,对于真实气体，你可以测量它，你能通过手指按在,自行车轮胎上来感觉到它。

麻省理工公开课 - 热力学与动力学课程节选