[Phys-L] Fwd: ?conservation of _internal_ energy

[Diego Saravia <dsa@unsa.edu.ar>]

Its obvious for me that any kind of energy, as internal energy is,  It 's
not conserved. You can convert one kind of energy into another. only total
is always conserved, if a body expands and lower its internal enegy and as
a consecuente other rises, the gravitacional energy of the rised body
grows. U is transformed to Potential Energy, E is conserved
> The distinction between U and E is significant in fluid dynamics.
> Maybe I'm missing something, but AFAICT the «internal energy» is
> not conserved.  To see this, consider the contrast:
> a) One parcel expands in such a way as to compress a neighboring
>   parcel.  U is conserved in this situation.  So far so good.
>  b) One parcel expands in such a way as to /lift/ a neighboring
>   parcel.  It seems to me that U is not conserved.

-- 
Diego Saravia
Diego.Saravia@gmail.com
NO FUNCIONA->dsa@unsa.edu.ar