Fluids and viscous flow

In summary, the conversation discusses a problem of finding the radius of a horizontal pipe with water flowing through it at a given volume flow rate. The formula Q = πR^4(P1-P2) / 8nL is used to solve for the radius, but there is confusion about the value of the differential pressure (P1-P2). After some discussion, it is determined that the correct formula to use is \DeltaP = \rhog\Deltah, where \Deltah is the difference in heights of the water columns. The correct answer is then obtained.
  • #1
maos
4
0

Homework Statement


Water (n = 1.00 10-3 Pa·s) is flowing through a horizontal pipe with a volume flow rate of 0.029 m3/s. As the drawing shows, there are two vertical tubes that project from the pipe. From the data in the drawing, find the radius of the horizontal pipe.

11_80.gif


Homework Equations



Q = πR^4(P1-P2) / 8nL


The Attempt at a Solution



0.029 = πR^4(0.045) / (8*10^-3 * .7)

solve for R, multiply by 100. However, i don't get the right answer...


What am i doing wrong? this seems like such a straightforward problem
 

Attachments

  • 11_80.gif
    11_80.gif
    4.3 KB · Views: 448
Physics news on Phys.org
  • #2
Is the differential pressure, (P1 - P2), in the formula given as the head (height or depth) of water (0.045 m), or is it pressure, in which case [itex]\Delta[/itex]P = [itex]\rho[/itex]g[itex]\Delta[/itex]h, where [itex]\Delta[/itex]h is the difference in heights of the water columns, i.e. 0.045 m.
 
  • #3
oh maybe it's pgh. let me give it a second go.
 
  • #4
yes i got it right. thank you Astronuc for the fast reply! I owe you :)
 

What is the difference between a fluid and a viscous flow?

A fluid is a substance that can flow and change shape when subjected to an external force, while a viscous flow is a type of fluid flow that is characterized by its resistance to deformation and ability to resist shear stress.

What are some examples of fluids and viscous flow in everyday life?

Some examples of fluids include water, air, and oil, while examples of viscous flow include honey, shampoo, and molasses. In everyday life, we can observe fluids and viscous flow in activities such as pouring a glass of water, blowing bubbles, and stirring a thick soup.

How does viscosity affect the behavior of fluids?

Viscosity is a measure of a fluid's resistance to flow. The higher the viscosity, the slower the fluid will flow. This can have various effects on the behavior of fluids, such as creating turbulence, affecting the rate of diffusion, and causing drag on objects moving through the fluid.

What is laminar flow and turbulent flow?

Laminar flow is a type of fluid flow in which the particles move in parallel layers, while turbulent flow is characterized by chaotic and irregular motion of particles. Laminar flow is typically observed in low viscosity fluids, while turbulent flow is more common in high viscosity fluids.

How is the flow rate of a fluid determined?

The flow rate of a fluid is determined by factors such as the viscosity of the fluid, the pressure applied, and the size and shape of the container or channel through which the fluid is flowing. It can be calculated using the equation Q = A * v, where Q is the flow rate, A is the cross-sectional area of the flow, and v is the velocity of the fluid.

Similar threads

  • Introductory Physics Homework Help
Replies
4
Views
908
  • Introductory Physics Homework Help
Replies
1
Views
1K
Replies
19
Views
955
  • Introductory Physics Homework Help
Replies
6
Views
1K
  • Introductory Physics Homework Help
Replies
15
Views
4K
  • Introductory Physics Homework Help
Replies
5
Views
1K
  • Classical Physics
Replies
4
Views
999
  • Introductory Physics Homework Help
Replies
5
Views
1K
  • Introductory Physics Homework Help
Replies
4
Views
1K
  • Introductory Physics Homework Help
Replies
11
Views
1K
Back
Top