Slow almost unchanging with respect to the

1
Equilibrium process Quasi-static process which
transforms the system through
states of thermal equilibrium
Slow (almost unchanging) with respect to the
typical relaxation times of a system
Equilibrium processes are represented by lines in
the state space
Constant volume (isochoric) processes
0
No work done
2
Constant pressure (isobaric) processes
Pconst.
Isothermal processes
Work done _at_ Tconst.
Tconst.
3
Adiabatic processes
No heat heat transfer in or out of the system
Q0
How to realize an adiabatic process
very good insulation
1
or
no time for heat to be exchanged
rapid changes in volume
2
0
?V?0
Note although the constant volume
specific heat appears, expression
applies to any process that starts
and ends in equilibrium
In the limit
?V?0
First order differential equation
?V?0
4
Solution of
by integration
with
with
different from constant above
5
What is the work done in an adiabatic equilibrium
process
during entire adiabatic process
Starting at P0 and V0
6
Graphic summary of various processes on a PV
diagram
Constant pressure (isobaric) process
Constant volume (isochoric) process
adiabatic process Q0
Constant temperature (isothermal) process
Isotherms for reference
Adiabat steeper than isotherm