Equipartition & Cp, Cv

Each DOF contributes ½kT.

Concept

Equipartition & Cp, Cv is a foundational idea in this chapter. The defining relationship is:

$C_p - C_v = R$

Monoatomic: γ = 5/3; Diatomic (rigid): γ = 7/5; Polyatomic: γ = 4/3.

Worked Application

Apply the formula to a typical problem from your textbook. Identify the knowns, plug into the equation, and check that the units work out. Always sanity-check the magnitude before accepting an answer.

Common Confusions

• Confusing the variables in the formula — re-read the symbol definitions in the chapter.
• Forgetting unit conversions (cm vs m, g vs kg).
• Ignoring sign conventions where direction matters.

Key Takeaways

• Master the formula $C_p - C_v = R$ and one canonical example.
• See the chapter index for full derivations, traps and exam-grade problems.