Problem Set 2

The problem set questions for chapter 6 have now been marked. Once Seth has approved them I will send out the commented pdf's to their respective authors (and yes James your hard copy has also made it into the digital age thanks to my trusty scanner!) Even though I haven't signed any confidentiality or non-disclosure agreements I am a very honorable person and will thus not be leaking your assignments to Assange.

There were two questions which no two people answered in the same way, never the less I through most were correct. They were 6A c. and 6B.

6A c. essentially asked you to show that at maximum entropy T1 = T2 for connected systems 1 and 2. The solution given by Nelson is a single line and combines equation 6.8 (p.203) with the result from 6A b., namely that E/N = 3kT/2, to get 0=1/T1 - 1/T2.

6B is something of a controversial question for me. The first two sentences make sense: show that entropy is extensive while temperature is intensive. The next two sentences on the other hand seem to be asking a completely different question. And even after going through Nelson's solution I still have no idea why he's used the approach he has. Given the ambiguity of the question (and Nelson's solution) I've effectivley marked it based on the first two sentences alone. That is, showing entropy to be extensive and temperature intensive.