Thermodynamics Overview — AP Physics 2
1. Unit at a Glance
We build this unit from foundational definitions to advanced applications. You will start by defining what a thermodynamic system is, learn core state variables and ideal gas behavior, then explore energy transfer, the two laws of thermodynamics, and end with entropy and the direction of thermal processes. Every concept connects to answering two key questions: how much energy is transferred, and why processes proceed the way they do.
Common Pitfalls
Why: Inconsistent sign conventions across sources lead to frequent calculation errors on the AP exam.
Why: The colloquial 'disorder' definition often leads to incorrect reasoning about entropy change in processes.
Why: The ideal gas law only holds for systems at thermal equilibrium, not during rapid non-equilibrium changes.