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This page was created as a result of a discussion in Talk:Thermodynamic_equations following major edits to that page. It was generally agreed to take the earlier table-of-equations content, starting with the last revision before the major change and move it to a new page named Table of Thermodynamic Equations. -- Pmetzger 16:54, 19 December 2006 (UTC)
Agreed. Hard Raspy Sci 04:44, 3 January 2007 (UTC)
Given that everything on the page is expressed in extensive quantities, why are the lower case 'w' and 'q' used for work and heat, respectively? If there is some rational for this choice, the definition for entropy is inconsistent. Otherwise, capital letters seem more appropriate and should be instituted throughout.
Thermodude
23:00, 10 July 2007 (UTC)
I have changed the sign in the equation for entropy. It comes from the fundamental thermodynamic relation: dF(T,V)=-SdT-PdV and dG(T,P)=-SdT+VdP. — Preceding unsigned comment added by 131.180.28.89 ( talk) 11:31, 2 November 2017 (UTC)
In the equation table for an ideal gas, shouldn't internal energy at a constant pressure be q - PΔV instead of q + PΔV (since U = q + w and w = -PΔV)? 199.8.26.10 14:43, 26 September 2008
The table says the general entropy equation is :
I find this suspicius, as for an ideal gas, the general equation for entropyp is dS=(Cp/T)dT - (R/P)dP. What happened to the last part of this equation? and how can the index on heat capacity C disappear, in my opinion it is not defined at all, without the index?
Also, could somebody with a more recent knowledge than I on this subject review the
ideal gas page, which has sidetracked into a lot of thermodynamics.
Power.corrupts (
talk)
13:26, 30 September 2008 (UTC)
The majority of texts use a sign convention of heat into the system is positive Q and work done by the system on its environment is positive W. I have changed equations to this convention. Examples of texts that follow this include Moran & Shapiro, Keenan, Cengel & Boles, Halliday & Resnick. An example of a book using the other convention for Work is Zemansky & Dittman. This sign convention makes sense in the context of a heat engine a la Carnot, where positive work is generated using positive heat, and is universal in the field of engineering, in my experience. Jdpipe ( talk) 01:18, 5 February 2009 (UTC)
This page is a random collection of equations from all over the place. I would like to pare this page down, organize it as a set of links to other pages and not repeat the equations here. As the main pages evolve, their statements of the equations change, but this page is not updated. It should not have to be. I have eliminated a few equations, leaving only their links to main articles. If this is ok, then we can continue the process until this page is just a collection of organized links.
It should be and instead of and in . Indeed, is simpler. Quaerendo I ( talk) 09:32, 27 May 2021 (UTC)
![]() | This article is rated List-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | ||||||||||
|
This page was created as a result of a discussion in Talk:Thermodynamic_equations following major edits to that page. It was generally agreed to take the earlier table-of-equations content, starting with the last revision before the major change and move it to a new page named Table of Thermodynamic Equations. -- Pmetzger 16:54, 19 December 2006 (UTC)
Agreed. Hard Raspy Sci 04:44, 3 January 2007 (UTC)
Given that everything on the page is expressed in extensive quantities, why are the lower case 'w' and 'q' used for work and heat, respectively? If there is some rational for this choice, the definition for entropy is inconsistent. Otherwise, capital letters seem more appropriate and should be instituted throughout.
Thermodude
23:00, 10 July 2007 (UTC)
I have changed the sign in the equation for entropy. It comes from the fundamental thermodynamic relation: dF(T,V)=-SdT-PdV and dG(T,P)=-SdT+VdP. — Preceding unsigned comment added by 131.180.28.89 ( talk) 11:31, 2 November 2017 (UTC)
In the equation table for an ideal gas, shouldn't internal energy at a constant pressure be q - PΔV instead of q + PΔV (since U = q + w and w = -PΔV)? 199.8.26.10 14:43, 26 September 2008
The table says the general entropy equation is :
I find this suspicius, as for an ideal gas, the general equation for entropyp is dS=(Cp/T)dT - (R/P)dP. What happened to the last part of this equation? and how can the index on heat capacity C disappear, in my opinion it is not defined at all, without the index?
Also, could somebody with a more recent knowledge than I on this subject review the
ideal gas page, which has sidetracked into a lot of thermodynamics.
Power.corrupts (
talk)
13:26, 30 September 2008 (UTC)
The majority of texts use a sign convention of heat into the system is positive Q and work done by the system on its environment is positive W. I have changed equations to this convention. Examples of texts that follow this include Moran & Shapiro, Keenan, Cengel & Boles, Halliday & Resnick. An example of a book using the other convention for Work is Zemansky & Dittman. This sign convention makes sense in the context of a heat engine a la Carnot, where positive work is generated using positive heat, and is universal in the field of engineering, in my experience. Jdpipe ( talk) 01:18, 5 February 2009 (UTC)
This page is a random collection of equations from all over the place. I would like to pare this page down, organize it as a set of links to other pages and not repeat the equations here. As the main pages evolve, their statements of the equations change, but this page is not updated. It should not have to be. I have eliminated a few equations, leaving only their links to main articles. If this is ok, then we can continue the process until this page is just a collection of organized links.
It should be and instead of and in . Indeed, is simpler. Quaerendo I ( talk) 09:32, 27 May 2021 (UTC)