Re: [Phys-l] question about Bernoulli

[John Mallinckrodt <ajm@csupomona.edu>]

Aha.  I knew it would take nothing more than hitting the send button to come to my senses.  Still, perhaps a fun question!

John Mallinckrodt
Cal Poly Pomona

On Nov 18, 2010, at 5:15 PM, John Mallinckrodt wrote:

> Another question about Bernoulli:
>
> The Bernoulli equation (for incompressible fluids) says that the sum of the kinetic energy density, the gravitational potential energy density, and the pressure is constant along a streamline so that if the speed DECREASES from point A to point B along a horizontal streamline, the pressure must be HIGHER at point B than at point A.
>
> But in the rest frame of the fluid at point A, the speed is zero at point A and, thus, necessarily is higher at point B so that, in THAT frame, the pressure must be LOWER at point B than at point A.
>
> What's up with that?
>
> John Mallinckrodt
> Cal Poly Pomona
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