# Thermodynamics Question.

1. Jul 13, 2010

### vslo

1. The problem statement, all variables and given/known data

I need help with this question here.
Its thermodynamics.
I dont know the enunciate for sure, but I explain it
1 mol of a monoatomic gas passes for the processes:

A->B->C

AB is a isothermal expansion process
BC is a constant pressure process(Loses volume)
CA is a constant volume process (gains pressure)

Pa=5Pc and Vb=5Vc
The answer is in Terms of Pc and Vc

a) The liquid work that the gas.
b) how mush heat does the gas yields?
c)hot much heat does the gas receives?
d) the efficiency of the process
e) compare its efficiency to a carnot machine with the same temperature variations.

2. Relevant equations

3. The attempt at a solution

2. Jul 14, 2010

### vslo

anyone?

3. Jul 15, 2010

### lightgrav

You need to treat each step in the process separately ... keep track of Q and W and Delta(I.E.) for each, so 9 entries.
The bookkeeping is not as bad as it sounds ... isotherm Delta I.E. = 0, for example, and constant Volume compression has W = 0 .
You should know formula for W during constant pressure - Look-up formulas for isotherm.