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Adiabatic vs isothermal: PV diagram

What you are seeing: two reversible processes from the same starting state. Isothermal: PV=nRTPV = nRT. Adiabatic: PVγ=PV^\gamma = const, which is steeper. Watch the gas piston compress and expand along the chosen curve, and the temperature track the volume.

Figure 1. Isothermal (cyan) vs adiabatic (orange) reversible processes from the same initial state.
γ (gas)1.40
T_0 (K)300
process

WHAT TO TRY

  • Vary each control and watch the rail readouts respond.
  • Compare the diagnostic plot against the live scene.