Solving Bernoulli Principle Homework: Water Flows in Pipe

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The discussion centers on solving a homework problem involving the Bernoulli principle and fluid dynamics in a pipe where water flows upward at a rate of 96 L/min. The pressure at the lower end is given as 80 kPa, with height differences of 10 m and 13 m at the respective ends. Participants are attempting to calculate the velocities at both ends and the pressure at the upper end using Bernoulli's equation and the continuity equation, but face challenges due to the lack of diameter information for the pipe. Clarifications are sought regarding the pipe's diameter and whether it is tapered or constant, as this affects the relationship between the velocities. The conversation emphasizes the need for additional details to accurately solve the problem.
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Homework Statement



Water Flows upward throw the pipe shown in the diagram at 96 L/Min. If the pressure at the lower end is 80kPa, find the velocity of the water is at both ends and the pressure at the upper end. Assume that the density of water remains constant throughout the tube and that h1= 10 m and h2 = 13m

Homework Equations


P1+ 1/2 ρv^2+gy1=P2+1/2ρv2^2+gy2

Continuity Equ:
A1V1=A2V2
(Tried to use this equation to hep me find the velocity but given their is no diameter or radius given to find the are it was a waste of time)

The Attempt at a Solution


volume flow rate up the pipe:
96L/min (1.0X10^3 cm^3/ 1.00L)(1.00m/100cm)^3(1.00min/60sec) = 1.6x10^3 m^3/s


Attempt to tried to use the Continuity Equation as substitution for one of the velocities:


A1V1=A2V2

V2(A2/A1)= V1

Substituting V1 in the Bernoulli Equation:
P1+1/2ρ(V2(A2/A1))^2+ρgy1=P2+1/2ρv2^2+gy2

2g(y^2-y1)=v2[1-(A2/A1)]

sqrt(2gh)/sqrt(1-(A2/A1)^2) =v2



Any help or guidance will be appreciated. Thank you.
 
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I can't see your diagram so if you could attached it maybe I can help.

I refer to the bernoulli's theorem as energy per unit weight:
(P_1/(rho*g))+(V_1^2/2g)+h1 = (P_2/(rho*g))+(V_2^2/2g)+h2
Q = 1.6x10^-3 m^3/s

By inspection of the pipeline, is it tapered or is the diameter constant? If it is constant what would be the relationship between V_1 and V_2?

A change of diameter should however should be stated if there is one... Is it a horizontal, angled or vertical pipe?
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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