Re: [Phys-l] App. for Was: Re: T dS versus dQ

[Brian Whatcott <betwys1@sbcglobal.net>]

John Mallinckrodt wrote:
> >  ..If one envisions a  
> > cylinder that is absolutely impervious to any energy transfer  
> > through its walls, fitted with a piston and containing Nitrogen  
> > only, and a stop inside the cylinder that prevents the piston from  
> > compressing the gas to less than half its original volume - and  
> > then one applies a force with one's hand to push the piston to the  
> > stop in 10 seconds - and then repeat with identical apparatus but  
> > do the compression in 0.001 seconds, and then let the two pieces of  
> > apparatus sit for a while until all waves. etc., dissipate, will  
> > there be any difference in their final states
> >     
>
> Yes.
>
>   
> > - and specifically what?
> >     
>
>
>   
> > The final volumes are identical, will the final temperatures and  
> > pressure be higher?
> >     
>
> Both will be higher than they would have been had the process been  
> quasistatic.
> See above.
>
> JM
>   
Interesting that John M is once again faced with an incredulous audience,
an audience accustomed to lab demos from a smiling professor figure
that show a step compression as "adiabatic".    
It's as though people could not grasp the difference between
laminar flow and turbulent flow.
What's the difference?
Entropy! Temperature! Turbulence!

Brian W