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 mouli1991 September 26, 2013 03:22

What is this conservation of energy

Im very bad in basics to understand

here all fluids --> Bernoulli's equation we got P+1/2 v^2/2+rho*g*h
Here instead of p can we insert Internal energy U as we do in First law of thermodynamics.
If yes, then can we say that Internal energy can also be any energy acting inside a system (Microscopic and macroscopic).
If no why is that?

 FMDenaro September 26, 2013 09:24

Quote:
 Originally Posted by mouli1991 (Post 453644) Im very bad in basics to understand here all fluids --> Bernoulli's equation we got P+1/2 v^2/2+rho*g*h Here instead of p can we insert Internal energy U as we do in First law of thermodynamics. If yes, then can we say that Internal energy can also be any energy acting inside a system (Microscopic and macroscopic). If no why is that?
Sorry, could you state your question in a more clear way?

Bernouilli is valid only for fluid of constant density and in absence of any dissipative action...

 truffaldino September 26, 2013 20:33

Quote:
 Originally Posted by mouli1991 (Post 453644) Im very bad in basics to understand here all fluids --> Bernoulli's equation we got P+1/2 v^2/2+rho*g*h Here instead of p can we insert Internal energy U as we do in First law of thermodynamics. If yes, then can we say that Internal energy can also be any energy acting inside a system (Microscopic and macroscopic). If no why is that?
It is enthalpy, not internal energy: Google Bernoulli equation for compressible flows or look corresponding section at

http://en.wikipedia.org/wiki/Bernoulli%27s_principle

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