The system's energy change is related to its internal energy
change AU,“ by“
ABS” = AEBLSYS + dcEP__5},s + AUSYS (5)
where Ek and Ep are changes of the system's
macroscopic kinetic and potential energies, respectively. in
the examples in this article, the system is stationary so that
Ek,s and Ep,s are zero; thus, Es and U,” are equal in
these examples.