- #1

adjurovich

- 53

- 11

Bernoulli equation (for this example) would go like this:

ρgh = 1/2ρv²

We are getting this result because the static pressures are equal to atmospheric so we can eliminate these two from equation, and the pressure on some elevation h (which isn’t actually hydrostatic pressure) is bigger than zero while on the ground (where this tiny hole is), h=0 so it is equal to zero. We can simply ignore the dynamic pressure on elevation h because the water level decreases much much slower than it flows through this tiny hole.

So my conclusion is that static pressure is actually sum of all external pressures (atmospheric pressure, piston pressure, etc) that push on fluid and cause its motion? Please correct me if I’m wrong.

Also, what happens to the ACTUAL hydrostatic pressure since ρgh is technically potential energy of fluid rather than its hydrostatic pressure.