H2 Physics 9478 · Topic 11

Thermal physics: gases, systems and energy transfer

Connect thermodynamic temperature and molecular motion to ideal-gas behaviour, internal energy, equilibrium, work, the thermodynamic laws and thermal-property energy balances.

  • H2 Physics 9478 (2027)
  • 6 lessons

Before you begin

Study each reviewed objective cluster, then use the recorded diagnostic and repair plan. H2 practice evidence remains separate from H1 and H3.

Be comfortable with: Energy & Fields objective chainQuantities & Measurement objective chain

Prove your understanding

Practice and repair

Recommended next stepH2 topic diagnosticCheck the reviewed objective clusters and build a qualification-specific repair plan.Start diagnostic
Key ideas and reference

Use this concise Thermal physics: gases, systems and energy transfer checklist to locate the right objective cluster. Full definitions, derivations and worked examples stay in the linked lessons.

  • Connect thermodynamic temperature and molecular motion to ideal-gas behaviour, internal energy, equilibrium, work, the thermodynamic laws and thermal-property energy balances.
  • Thermodynamic temperature and Celsius conversion 12(a)–(b)
  • Ideal-gas equations, particles and moles 12(c)–(d)
  • Kinetic model, pressure derivation and molecular energy 12(e)–(g)
  • Internal energy, temperature and thermal equilibrium 13(a)–(c)
  • Work, zeroth law and first law 13(d)–(f)
Course coverage and review details

Topics 12 and 13 state no explicit exclusions. They remain separate official topic identities in one shared Thermal Physics route. The first-law convention is ΔU = Q + W, where W is work done on the system; for expansion against constant external pressure, work done by the gas is pΔV and work done on the gas is −pΔV.

Coverage is reviewed against 9478 topic 12(a)–(g), PDF page 21; topic 13(a)–(g), PDF page 22. Selected-response progress does not by itself prove constructed, diagrammatic or practical performance.

Reviewed 2026-08-01