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Homework Statement
The following image shows the parts A and B of a pipe where the middle part goes under a hill the length of both parts A and B is 30m and the diameter of them each is 2cm where as the middle part has a length of 110m to determine the middle part's diameter one engineer decided to push water in the pipe with a speed of 2.50 m\s in part A he dropped a small coin in the flow and noticed that it took 88.8 seconds for it to start from A and exit from B.
1)calculate the diameter of the middle pipe
Homework Equations
v=d\s
A1*v1=A2*v2. (Continuity equation)
A=pi*r^2[/B]
The Attempt at a Solution
Finding the area of a and b:
0.02^2*pi=0.00125m^2
Finding the time it would take to travel through A and B (not including mid pipe)
2.50=30/s
s=12
So for a and b it would take 24 seconds
For mid part it would take 88.824=64.8
Mid part speed
110/64.8=1.697m\s
So
0.00125*2.50=1.697*A2
Area=0.001841
0.0018141=pi*r^2
R=0.024m
Answer sheet says that the diameter is 3.60cm
help!
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