We want to integrate. So let's take the integral of both sides, going from the initial point to the final point.
分别从初态,到末态做积分,消去微分。
The reason for inexact doesn't mean it's a crummy measurement, t means that it's path dependent, and so the value of this integral depends on how you get from one to two.
这是因为它是,与积分路径有关的,因此这里的积分值,取决于从一端到二端的,具体路径。
And so just like here, w2 now q2 is minus w2, that's integral going from three to four p dV.
就跟这儿一样,现在是q2等于负,等于从第三点到第四点过程的pdv的积分。
So we can put that in here and do this integral.
因此把压强带入到这里,算出积分。
So it's, this is just the integral pdv And it's an ideal gas, isothermal, right.
从一点到二点的,的积分。,from,one,to,two,of,p,dV。,这是理想气体,恒温过程,好的。
du So, we can also write delta u as integral from 1 to 2 of du.
我们也可以将Δu写成,从1到2的积分。
V2 p1 times V2 minus V1. What that turns out to be, 0 this area right here. It's V1 minus V2 times p1.
第二步做的功是-pdV,积分从V2到,这部分积分出来是多少?应该是。
The ideal gas constant doesn't change, temperature doesn't change, and so v we just have minus nRT integral V1, V2, dV over V.
理想气体常数不变,温度也不变,因此,是负的nRT,积分从v1到v2,dv除以。
So, the work for this process is the integral, pdv or minus the integral, V1, V2, p dV.
此过程中的做功等于负的积分,从v1到v2,外部。
V1 This first integral is zero V1 to V1, then I get minus p2 times V2 minus V1 or p2 times V1 minus V2. Again, 0 a positive number.
先保持体积为,对pdV积分1,然后对p2dV从V1到V2积分,第一部分积分为。
/T We've got Cv integral from T1 to T2, dT over T is equal to minus R from V1 to V2 dV over V.
左边是Cv乘以,从T1到T2对dT积分。
So, if you're doing physics, x2 work is the integral of force, dx, x1 to x2.
如果你正在干活,功就是力的积分,从x1,到。
So it's nR integral from V1 to V2 dV over V.
即nR除以V乘以dV从V1到V2的积分。
That's equivalent to doing the integral, and so, what we end up getting is that the reversible work v2 pdv is equal to minus integral V1, V2, p dV.
这与刚才的积分过程效果相同,最后,我们得到的结论是可逆过程的功,是负的积分,从v1到。
V2 That's minus p1 times V2 minus V1.
做的功是-p1dV,积分从V1到。
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