Bernoulli's equation to find pressure in a pipe above water surface of tank

Worked example of using Bernoulli's equation to find the pressure in a pipe above the water surface of the tank.

[dhxl]

That's interesting. Z1 = U2^2 / 2g => U2 = (Z1 · 2 · g)^0, 5. In terms of distance travelled. It can be easily checked that free falling object gains speed at 9, 81 m/s/s rate. Thus after 1 second of movement its speed will be 9, 81 m/s and it will travel 4, 905 m. Let's check it. U2 = (4, 905 · 2 · 9, 81)^0, 5 = 9, 81. And, as we can see, it doesn't depend on the pipe diameter.

[gelomelo]

Hi. What does negative pressure mean at point x ?