Calculating the Pressure at a Reservoir

[tomtomtom1]

Summary:: Calculating the Pressure at a Reservoir

Hello all

I am struggling to calculate the pressure at a given point, i am getting all sort of strange answers and i was hoping someone could help.

The question is as follows:-

From this i have tried to draw a sketch of the problem (not sure if its correct though):-

I have tried to use the formula Q = vA and Bernoullis principle to calculate the pressure at P2 by doing the following:-

But i have been told that this is incorrect and the correct answer is -49.5 kN/m^2

Because the pressure and velocity at P1 is 0.

I was wondering if i could get someone elses view?

Thank you.

 

[Chestermiller]

P1 should not be situated inside the pipe. It should be situated at the reservoir surface, at its interface with the atmosphere.

 

[rude man]

Summary:: Calculating the Pressure at a Reservoir

Hello all

I am struggling to calculate the pressure at a given point, i am getting all sort of strange answers and i was hoping someone could help.

The question is as follows:-

View attachment 254525

From this i have tried to draw a sketch of the problem (not sure if its correct though):-

View attachment 254526I have tried to use the formula Q = vA and Bernoullis principle to calculate the pressure at P2 by doing the following:-View attachment 254527

But i have been told that this is incorrect and the correct answer is -49.5 kN/m^2

Because the pressure and velocity at P1 is 0.

I was wondering if i could get someone elses view?

Thank you.

How did you manage two alternative answers? The equation is 1st, not 2ne, order!
Also of course see post 2.