Classical thermodynamics problem.

[Dimitri Terryn]

Hm, I'm pretty much stuck on a thermodynamics problem.

If you consider two identical masses of water at temperatures T1 and T2, what is the global increase in entropy after they have reached thermal equilibrium.

The best I could come up with is [del]S = m*C*ln(T2/T1).

The answer listed in the book is 2m*C*ln[(T1+T2)/2Sqrt(T1*T2)]

I am completely and utterly stuck. Any help would be greatly appreciated.

-Dimi

[Mulder]

This will probably be moved to HWK. help, but think about what the equilibrium temperature is, and the change in Entropy of each block.

[Dimitri Terryn]

Yes, that's it. I've got it. Thanks.