Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: [Phys-l] T dS versus dQ

I still don't see how this experiment is relevant to the question at hand: the question was (I thought) whether fast or slow made a difference in the final temperature for an insulated piston. But this device is clearly not insulated, so it seems to me that the apparatus demonstrates that a quick compression, happening fast enough to be modeled as adiabatic, causes a temperature increase, where a slow one remains at the same temp. [Do we then say that the work in equals the heat out? I know my textbook says that...] This is an interesting demo, but the original question is not being tested.

-----Original Message-----
From: phys-l-bounces@carnot.physics.buffalo.edu [mailto:phys-l-
bounces@carnot.physics.buffalo.edu] On Behalf Of LaMontagne, Bob
Sent: Friday, January 15, 2010 11:53 AM
To: Forum for Physics Educators
Subject: Re: [Phys-l] T dS versus dQ

I'll go back and try that on one. We have a dozen setups and I always thought
the stiffness was a "feature" to keep everything isothermal :-)

Bob at PC

-----Original Message-----
From: phys-l-bounces@carnot.physics.buffalo.edu [mailto:phys-l-
bounces@carnot.physics.buffalo.edu] On Behalf Of Bernard Cleyet
Sent: Friday, January 15, 2010 2:26 AM
To: Forum for Physics Educators
Subject: Re: [Phys-l] T dS versus dQ

Have you tried grease?

I'd replace the shaft w/ an unthreaded one and add a sleeve to the top
plate, so one may even do "mixing" in addition to quasi-adiabatic
compression (rarefaction).



On 2010, Jan 14, , at 21:03, LaMontagne, Bob wrote:

Maybe ours are just stiffer than yours to turn.

_______________________________________________
Forum for Physics Educators
Phys-l@carnot.physics.buffalo.edu
https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l
_______________________________________________
Forum for Physics Educators
Phys-l@carnot.physics.buffalo.edu
https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l