When we compare the rapid expansion of an ideal gas to a very slow expansion from an initial state to a final state, we categorize one as irreversible and the other as reversible. This distinction arises because, during a slow expansion, the gas is either in or close to a state of equilibrium, which makes it easier for the process to be reversed. Conversely, in the case of a rapid expansion, there is a pressure imbalance that requires additional work to reverse the process.
So, what is the relationship between thermodynamic equilibrium and reversibility? And what do we mean by pressure imbalance in this context? How does this concept work?
Note:My question is if the first process is reversible only because no extra work is requiredto return to final state, then why would the second process not be the same? What led to that conclusion. How does the imbalance between external and internal pressure work in this context?
