The work done by Thermodynamic processes

AI Thread Summary
The discussion focuses on classifying thermodynamic processes based on the work done during compression or expansion. The ranking of work done from highest to lowest for an ideal gas is adiabatic, isothermal, and isobaric. The work done can be calculated using the formula W = ΔU - Q, where Q is the heat flow, which is zero during compression. The internal energy change is related to temperature and pressure-volume changes. The clarification of reversible processes was acknowledged, enhancing understanding of the topic.
AhmedHesham
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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
 
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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
 
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