The work done by Thermodynamic processes

Click For Summary

Discussion Overview

The discussion revolves around the classification of thermodynamic processes in terms of the work done during compression or expansion, specifically comparing processes like isentropic and isobaric. Participants explore how different processes rank in terms of work done on an ideal gas.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant seeks to understand how thermodynamic processes can be classified based on the work done during compression or expansion.
  • Another participant provides a ranking of work done for ideal gas compression, suggesting that adiabatic processes result in the highest work done, followed by isothermal and isobaric processes.
  • A later post seeks clarification on whether the inquiry pertains specifically to reversible processes.
  • One participant expresses gratitude for the responses and indicates that they now understand the topic better.

Areas of Agreement / Disagreement

The discussion includes varying interpretations of the original question, and while some participants provide rankings of work done, there is no consensus on the classification criteria or the specifics of the processes being compared.

Contextual Notes

There are assumptions regarding the ideal gas behavior and the nature of the processes (e.g., reversible vs. irreversible) that are not fully clarified. The ranking of work done is dependent on these assumptions.

AhmedHesham
Messages
96
Reaction score
11
Hi gentlemen
I want to know the classification of thermodynamic processes according to which is higher than which in work done during either compression or expansion.
Thermodynamic processes like isentropic and isobaric.
Thanks
 
Engineering news on Phys.org
Hi Ahmed. (try to avoid gender specific salutations. PF welcomes people of all genders). Your question is not very clear. If you want to compare a compression of the same quantities of an ideal gas at the same initial volume and pressure to the same final volume using different processes, the ranking from highest to lowest amount of work done would be:
Adiabatic;
Isothermal;
Isobaric.

Since they begin at the same internal energy and since there will be no heat flow into the gas during compression, you can determine the amount of work done by comparing the change in internal energy using:
##W = \Delta U - Q## where W is the work done ON the gas and Q is the heat flow INTO the gas

Since there is no heat flow into the gas, Q ≤ 0.

The internal energy of an ideal gas is proportional to T and PV: ##\Delta U = nC_v\Delta T = (C_v/R)\Delta(PV)##

AM
 
Last edited:
AhmedHesham said:
Hi gentlemen
I want to know the classification of thermodynamic processes according to which is higher than which in work done during either compression or expansion.
Thermodynamic processes like isentropic and isobaric.
Thanks
I assume you are asking about reversible processes, correct?
 
Thank you very much guys for answering
I now understand it
 

Similar threads

Replies
1
Views
1K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 3 ·
Replies
3
Views
11K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
3
Views
3K
  • · Replies 2 ·
Replies
2
Views
4K