Results were generally significantly better. There was a big increase in the number who can find work done by a process represented by simple path, but a lot of the improvement came in the plugging and chugging.
Remember the primary goal of thermodynamics is to see how to convert thermal energy into work of a mechanical nature. Most of you showed you can find work for a simple case and many of you handled the tough adiabatic realtions between volume and pressure quite well. This is real progress and we have accomplished a lot.
Too many still cannot figure out what must happen to Q, W, and U for a given type of process (the first four questions).
Many of you had adiabatic expansions in problem 1 with rising temperatures and increased U. Where did this energy come from? How could an expanding gas do work ( as an expanding gas must) and gain energy rather than losewhen no heat was added?
Too often, you are still not thinking about energy conservation . You are just recording whatever results you get from hitting ( often the wrong) keys without understanding their meanings and implications.
Not enough of you showed that work out must come from loss of U in an adiabatic process, i.e. Wout = - delta U
Too few got the heat transfer problem right despite having the equation in front of you.
Some of you are still confusing R and k. Volume of 10^29 should be a tip off that you've made an error.
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