What Determines the Flow Speed in Differently Sized Horizontal Tubes?

Click For Summary

Homework Help Overview

The problem involves fluid dynamics, specifically the flow of seawater through two horizontal tubes of different diameters and the relationship between pressure and flow speed. The original poster presents a scenario with given diameters and a pressure difference, seeking to determine the flow speed in the larger tube.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the application of Bernoulli's equation and the conservation of mass in relation to the flow speed in the two tubes. Questions arise regarding the interpretation of constants in the equations and the relationship between fluid speed and tube diameter.

Discussion Status

Participants are exploring different aspects of fluid dynamics, with some providing guidance on relevant equations. There is an ongoing clarification of concepts, particularly regarding the conservation of mass and its implications for the problem at hand.

Contextual Notes

There is an indication of stress affecting the original poster's ability to engage with the problem, which may influence their understanding of the concepts involved. The discussion also highlights potential gaps in knowledge regarding the application of fluid dynamics principles.

Hypnos_16
Messages
148
Reaction score
1

Homework Statement



Seawater flows through a horizontal tube of diameter 3.00 cm that is joined to a second horizontal tube of diameter 1.70 cm. The pressure difference between the tubes is 7.25 kPa. What is the speed of flow in the first tube?

Homework Equations



I thought it was P1 + 1/2 pv2
turns out it isn't

The Attempt at a Solution



i don't know if it's cause I'm stressed, or just missing something, i cannot get this question to work.
 
Physics news on Phys.org
Note: P1 + 1/2 p v1^2 = constant = P2 + 1/2 pv2^2.

Do you also need to apply the conservation of mass ?
 
The conservation of mass? and what "Constant" are you talking about there?
 
The conservation of mass will allow you to relate the speed of the fluid in the two different size pipes and the pipe diameter.

Bernoulli's equation says P + p v^2 / 2 + p g h = constant. So if you know these values at one point, you know them at the other.
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
2K
Replies
10
Views
4K
  • · Replies 9 ·
Replies
9
Views
2K
Replies
1
Views
2K
  • · Replies 13 ·
Replies
13
Views
3K
Replies
1
Views
2K
  • · Replies 10 ·
Replies
10
Views
4K
Replies
2
Views
8K
  • · Replies 6 ·
Replies
6
Views
9K
  • · Replies 48 ·
2
Replies
48
Views
6K