So now if I look at my V1 over V2 to the gamma minus 1, that's T2 over T1.
于是把^=中2,的两个温度。
So when I expand this gas adiabatically and it cools down, why do you think it might cool down?
现在我们知道了气体绝热膨胀时,温度会下载,为什么会降温?
We control how we use time, we control the temperature in the environment, and hermetically seal ourselves in things.
我们控制时间的利用,我们控制周边环境的温度,我们把自己封闭在各种事务中,与世隔绝。
That is to say brick work in high temperature furnaces, maybe tiles on the Shuttle, to resist high temperatures because of the high internal bonding.
它在能够承受高温炉的温度,例如瓷砖,能够耐受高温,因为它们有强的内部键作用。
- And now temperature in Fahrenheit -- 212 all right, let's go ahead and pick an easy one like 212, Enter, and indeed equals 100 in Celsius.
现在输入华氏温度-,好的,让我们选一个简单的,像,回车,确实等于100摄氏度。
That's another invention of the 1600s, by the way-- the thermometer. And they learned that concept-- perfectly natural to us--temperature.
顺便说一下,温度计也是十七世纪的发明,那时候的人才刚刚开始理解温度的概念,虽然对我们来说这是个很自然的概念
When the temperature gets above the level you want it to be.
就在当温度超过你想要的温度时
That means that this temperature right here is the absolute lowest temperature you can go to that physically makes any sense.
是物理上不可能的状态,也就是说这一点,对应的温度是物理上。
For a real gas it depends on more than the temperature STUDENT: Are there any other constraints similar to that .
而对实际气体,这是不对的,它的内能不仅仅依赖于温度,学生:有其他,类似的约束吗?
Yet, the temperature goes up. So, I can have a temperature change which is an adiabatic temperature change.
它与外界不会,有物质或者能量的流动,然而系统的温度升高了。
How to go from one reference point to the other with this property. This property, f which we're going to call f.
这两个参考点插值,得到不同温度时工作物质的特性,我们把这一特性记做。
It sounds pretty silly, but it's really important because it allows you to define a thermometer and temperature.
这听起来相当白痴,但是它确实很重要,因为它让你可以定义,温度计和温度。
It's going to have some volume, temperature to begin with, and then we're going to do something to it.
气体有一定的,体积与温度,现在我们。
That is, most processes that we're concerned with, they'll happen with something held constant like pressure or temperature or maybe volume.
这句话是说我们所关注的大部分过程,发生的时候都是保持某个量为常数,比如压强,温度或者体积。
It allows you to define the concept of a thermometer. You have three objects, one of them could be a thermometer.
从热的物体流向冷的物体,由此我们可以定义温度,我们还可以用它来定义温度计:
OK, for most gases, T inversion is much 300K greater than 300 degrees Kelvin. Much greater than room temperature.
好,对大多数气体,转变温度都高于,比室温高很多。
And that property could be the volume, like if you have a mercury thermometer , the volume of the mercury.
这种性质可以是体积,如果你有水银温度计,水银的体积。
We could just collect a bunch of data. For a material .What's the volume it occupies at some pressure and temperature?
对一种物质我们可以得到一系列测量数据,在给定的温度和气压下,它的体积是什么?
So he grabbed his thermometer, and went and made a couple of measurements and discovered the first law of thermodynamics.
所以他拿来了温度计,进行测量,后来就发现了热力学第一定律。
In principle, this value, this efficiency, can approach 1 as the low temperature approaches absolute zero.
这个值,效率,当低温热源的温度1,是据对零度时可以达到一。
And you already saw last time there was this relationship between the temperature and volume changes along an adiabatic path.
是条绝热路径,而上次你已经看到,沿着绝热路径温度和体积,的变化有这个关系。
If you double everything in the system, the temperature is not going to change, it's not going to double.
如果你把系统中所有的东西增加一倍,温度是不会变的,它不会跟着增加一倍。
And that will end up winning out at basically any realistic temperature where the stuff really is a gas.
在体系仍然处于气体状态的温度下,熵战胜了能量。
Your plant is going to blow up, because the ideal gas law works only in very small range of pressures and temperatures for most gases.
理想气体定律,只在一个很小的压强,与温度的范围内适用。
Whereas under these conditions, these quantities, if you look at free energy change, for example at constant temperature and pressure, H you can still calculate H.
但是,在这些条件下,这些物理量,如果我们考察自由能的变化,例如在恒定的温度和压强下,我们仍然可以计算。
B=0 There's going to be some temperature where B is equal to zero. In that case, your gas is going to look awfully like an ideal gas.
在某个温度,这时,实际气体的表现,十分接近理想气体,高于这一温度它是正的。
And in particular let's look at, for example, du/dV du/dV at constant temperature.
更特殊一点考察,恒定温度下的。
For instance, the pressure and the temperature, or the volume and the pressure.
比如压强和温度,或体积和压强。
And so, again, we see a temperature increase, and we know the work, and the temperature increase, it's a constant pressure thing.
好,我们看到温度升高了,然后我们有做功量和温度的升高量,这是一个恒定压力下的值。
There's a volume, there's a temperature, than the pressure here. There's other volume, temperature and pressure here, corresponding to this system here.
温度等状态函数有本质区别,这个状态有一组,确定的体积,温度与压强。
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