Calculate Pressure Difference: Water Flow Through Tubes of Different Radii

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To calculate the pressure difference between a large tube and three smaller tubes, the continuity equation and Bernoulli's principle are applied. The initial velocity in the large tube is given as 2 m/sec, and the water falls a vertical height of 1.2m. The user calculated the velocity in the smaller tubes to be 18 m/sec but is unsure about the resulting pressure difference, which they found to be 148240 N/m^2. They are advised to reconsider their calculations, particularly the impact of the water flowing into three smaller tubes. Accurate application of these principles is crucial for determining the correct pressure difference.
daisyi
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I feel like I am getting so close to this one, but the answer just isn't right!

Water flows down a tube of radius R for a vertical height h into 3 tubes of radius R/3. If the water falls a distance of 1.2m and the velocity in the large tube is 2 m/sec, find the pressure difference between the large and small tubes.

so what I did is use the continuity formula to calculate the velocity of the other tubes, which is 18.

i then used bernouilli's equation to calculate the difference in the pressure, using the information provided and the velocity of 18 which i found above.

i keep coming up with 148240 N/m^2, which is way off of the answer! help!
 
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daisyi said:
so what I did is use the continuity formula to calculate the velocity of the other tubes, which is 18.
Redo this calculation. Don't forget that the water flows into three small tubes.
 
Last edited:
thanks a ton, got it
 
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