Speed in Larger and Smaller Tube

In summary, the conversation discusses a constricted horizontal tube that tapers from a radius of 4.00cm to 2.50cm. The question asks to find the speed of water in the smaller tube, as well as the water pressure difference between the two tubes. The solution involves using Bernoulli's principle, with the equation ΔP = 0.5ρ(v2^2 - v1^2). The final result is a speed of 8.96 m/s in the smaller tube and a water pressure difference.
  • #1
MoBaT
5
0

Homework Statement


A constricted horizontal tube of radius r1 = 4.00cm tapers to a tube of radius r2 = 2.50cm. If water flows at a speed 3.50m/s in the larger tube, (A) find its speed in the smaller tube. (b) Find the water pressure difference ΔP=ΔP1-ΔP2 in kPa and in atm.


Homework Equations



I have no clue.

The Attempt at a Solution



Succeeded in doing part A.

A1V1 = A2V2

V2 = (A1V1)/A2 = (pi(4)^2(3.50)) / (pi(2.50)^2) = 8.96 m/s
 
Last edited:
Physics news on Phys.org
  • #2
Venturi effect?
 
  • #3
You need to use Bernoulli's principle . The water speeds up and therefore gains KE.
This gain in KE comes from a decrease in PE (pressure)

ΔP = 0.5ρ(v2^2 - v1^2) ρ = density of water
(this is bernoulli's principle in its simplest form with the tube horizontal)
 
Last edited:

What is the relationship between speed and tube size?

The relationship between speed and tube size is inverse. This means that as the tube size increases, the speed decreases. Conversely, as the tube size decreases, the speed increases.

Why does speed decrease in larger tubes?

Speed decreases in larger tubes because there is more surface area for the fluid to come in contact with. This creates more friction and resistance, slowing down the fluid flow.

Why does speed increase in smaller tubes?

Speed increases in smaller tubes because there is less surface area for the fluid to come in contact with. This creates less friction and resistance, allowing the fluid to flow faster.

How does fluid viscosity affect speed in tubes?

Fluid viscosity, or the thickness of the fluid, affects the speed in tubes. The higher the viscosity, the slower the speed will be. This is because thicker fluids have more resistance to flow.

Is there a limit to how fast fluid can flow in a tube?

Yes, there is a limit to how fast fluid can flow in a tube. This limit is known as the critical velocity, and it is the point at which the fluid starts to become turbulent and loses its smooth flow. The critical velocity is affected by factors such as tube size, fluid viscosity, and surface roughness.

Similar threads

  • Introductory Physics Homework Help
Replies
1
Views
3K
  • Introductory Physics Homework Help
Replies
2
Views
7K
  • Introductory Physics Homework Help
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
1
Views
5K
  • Introductory Physics Homework Help
Replies
1
Views
2K
  • Introductory Physics Homework Help
Replies
4
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
6K
  • Introductory Physics Homework Help
Replies
1
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
1K
  • Introductory Physics Homework Help
Replies
11
Views
3K
Back
Top