A quasistatic process is an idealized thermodynamic process that occurs infinitely slowly, allowing the system to remain in or very close to equilibrium at every stage.
Key characteristics:
- The process proceeds so gradually that the system adjusts internally at each step, maintaining uniform pressure, temperature, and other properties.
- Because equilibrium is preserved, state variables like pressure, volume, and temperature are always well-defined.
- In practice, no real process is truly quasistatic, but it’s a useful approximation for analyzing reversible processes in thermodynamics.
Examples:
- Slowly compressing a gas with a piston so that its temperature and pressure adjust evenly throughout.
- Slow heat exchange between two bodies at slightly different temperatures.
Quasistatic processes provide the foundation for defining reversible work and understanding maximum efficiency in thermodynamic cycles like the Carnot engine.