Non-quasistatic process. Constant pressure.Work cero.

AI Thread Summary
In a non-quasistatic process with constant pressure, work is not necessarily zero; it depends on the change in volume. Work is calculated using the formula P ΔV, where P is the pressure and ΔV is the change in volume. If the volume remains constant, then the work done is zero. However, if there is a change in volume, work is performed even in a non-quasistatic process. Understanding these distinctions is crucial for analyzing thermodynamic systems.
Phyba
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If in a non-quasistatic process the pressure is constant, is the work necessarily equal to cero?
I have from the notes taken in class that it must be 0, but I don't really see why, so I'm not sure whether maybe I didn't hear it well.
I haven't really started to work with non-quasistatic processes yet; we were just given the definition of quasistatic process the other day.

Thanks!
 
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Phyba said:
If in a non-quasistatic process the pressure is constant, is the work necessarily equal to zero?
No. The work is zero if the volume is constant. The work done by the gas at constant pressure is ##P \Delta V##, but P is defined only if the process is quasistatic.
The work done on the gas by the surrounding atmosphere at pressure P is ## - P \Delta V##.

ehild
 

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