- #1
laminar
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There is a pipe whose diameter narrows smoothly from 10cm to 5.0cm. The pressure at where this pipe's diameter is 5cm is 50kPa. Given water's density of 1000kg/m^3, and a flow rate of 5.0L/s, what is the pressure at the point where the pipe's diameter is 10cm?
First the continuity equation:
Q=Av
0.005L/s=[pi(0.05/2)^2]v
v=2.546m/s
Then, Bernoulli's equation:
Substitute v1 for A2v2/A1
P1=50000+(.5)(1000)(2.564^2-[(pi*.05^2)(2.564)/(pi*.1^2)])
I left the potential energy out of the equation because it is negligible givien the number of significant figures we have. Even though I did the calculation with adding potential energy it is still wrong.
So I got 79993Pa. I know it is very wrong but I cannot check it since I don't have the answers. Any help please?
First the continuity equation:
Q=Av
0.005L/s=[pi(0.05/2)^2]v
v=2.546m/s
Then, Bernoulli's equation:
Substitute v1 for A2v2/A1
P1=50000+(.5)(1000)(2.564^2-[(pi*.05^2)(2.564)/(pi*.1^2)])
I left the potential energy out of the equation because it is negligible givien the number of significant figures we have. Even though I did the calculation with adding potential energy it is still wrong.
So I got 79993Pa. I know it is very wrong but I cannot check it since I don't have the answers. Any help please?