What is the Pressure Change in a Pipe for Salt Water Transport?

[mailmas]

Homework Statement

A pipe has a square cross section and a width of 2.00 m and is used to transport salt water from the ocean into a desalination plant. If a pump pushing the water into the pipe at a depth of 1.00 m below the surface of the ocean does so with a pressure of 80 kP a, and the dimensions of the pipe doesn’t change, what is the pressure in the pipe when it gets into the plant at a height of 5.00 m above the surface of the ocean?

Homework Equations

A*v=A*v
P1+1/2p*v^2 + pgy = P2 + 1/2p*v^2 + pgy
P_2 = P_1 + p*g*(y_1 - y_2)[/B]
p_saltwater = 1030 kg/m^3

The Attempt at a Solution

P_2 = P_1 - p*g*(4)
= 80000 + (1030)(9.81)(4) = 39582.8 [/B]

 

[haruspex]

P_2 = P_1 - p*g*(4)

4? Read the question more carefully.

 

[mailmas]

4? Read the question more carefully.

80000 - (1030)(9.81)(6) = 80000 - 60625.8 = 19374.2

 

[haruspex]

80000 - (1030)(9.81)(6) = 80000 - 60625.8 = 19374.2

Looks better, but you quote too many significant figures.

 

[mailmas]

Looks better, but you quote too many significant figures.

19400 Pa

 

[haruspex]

19400 Pa

Looks fine.