[Unified-mailman] Fwd: Unified students' confusion

[Ian Waitz]

Dear Unified students,

Please review the following note from Nivair regarding the 
assumptions for pv^gamma = constant.  I will also review this in 
lecture.

Best wishes,

- Ian

>
>
>Dear Professor Waitz,
>
>As I was grading T4, I noticed one thing that I thought I should 
>mention to you. This was a heavily conceptual problem, and a lot of 
>students seemed to be having trouble with one thing in particular. 
>Since this is also something I noticed a lot people asking about 
>when I did PRS for Wednesday's lecture, I thought I should tell you 
>in case you have time to clear it up on Monday.
>
>They all seem to want to use PV^gamma = constant (or the equivalent 
>P/T relation), either for all situations or for just situations that 
>are quasi-static. It seems like almost nobody knows that that 
>relation is only applicable for an ideal gas undergoing an adiabatic 
>quasi-static process, which is worrisome considering they'll soon be 
>taking a test on this material!
>
>I remember you clarifying that last year, too, and maybe this is a 
>common source of confusion and I'm worrying about nothing.  For what 
>it's worth, though, I think that's a big issue.
>
>Thanks!
>
>Nivair

-- 
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M A S S A C H U S E T T S  I N S T I T U T E  O F  T E C H N O L O G Y

Ian A. Waitz                       
Professor, MIT Department of Aeronautics and Astronautics
website: http://web.mit.edu/aeroastro/people/waitz/

Director of the Partnership for AiR Transportation Noise and 
Emissions Reduction (PARTNER)
website: http://mit.edu/aeroastro/partner

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