Adiabats versus Isotherms - Quick clarification

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SUMMARY

The discussion clarifies the distinction between isothermal and adiabatic processes in thermodynamics, specifically in the context of a gas cylinder with a piston. The first scenario, where the piston is pushed in slowly, is correctly modeled as an isothermal process due to sufficient time for heat transfer, while the second scenario, with a quick push, is modeled as an adiabatic process since it occurs too rapidly for heat exchange. The importance of considering external conditions, such as the presence of a fixed-temperature heat reservoir, is emphasized for accurate modeling.

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Homework Statement


I'm doing a problem about a cylinder containing a gas. A piston attached to the cylinder is
1) pushed in slowly
2) pushed in quickly

Before I continue with the problem, I want to make sure that my assumptions are correct.

I am going to model 1) as an isothermal process. It goes slowly enough that the system's temperature stays the same as it has time to transfer heat from the outside.

I'll model 2) as an adiabatic process. It's fast enough that no heat is transferred between the system and the surroundings.

Homework Equations





The Attempt at a Solution


Is my understanding of this correct? I am not entirely clear on isothermal vs adiabatic processes...
 
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It sounds like you understand the difference between isothermal and adiabatic processes.

Does the problem specify that the system (cylinder) is surrounded by a fixed-temperature heat reservoir? If not, you have to think more carefully about the heat transfer in (1).
 
My thermal physics professor has put it into those terms often, that 'slowly' indirectly means 'isotherm' and 'quickly' indirectly means adiabat, for precisely the reasons you said. So I believe you are correct in assuming that, given no other specific information but what you posted. If the question were more in-depth with more details, it would not be a good idea to jump to those conclusions before analyzing the entire situation. But a vague, more general question, I believe that would be perfectly reasonable to assume.

[I know I'm just a student myself and not an 'expert' but I thought it wouldn't hurt to share.]
 

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