Bernoulli's Equation and stream of water

Click For Summary
SUMMARY

The discussion focuses on applying Bernoulli's Equation to determine the diameter of a water stream 13.0 cm below a faucet opening. The initial diameter of the stream is 1.20 cm, and the flow rate is calculated as 125 cm³ in 18.2 seconds, resulting in a velocity of 6.078 cm/s. The key equations utilized are A1v1 = A2v2 for flow continuity and the Bernoulli equation for energy conservation. The solution involves calculating the final speed and subsequently determining the necessary diameter to maintain the same volume flow rate.

PREREQUISITES
  • Understanding of fluid dynamics principles, specifically Bernoulli's Equation.
  • Familiarity with the concept of volume flow rate and its calculation.
  • Knowledge of area and velocity relationships in fluid flow (A1v1 = A2v2).
  • Basic algebra and geometry for solving equations involving diameters and areas.
NEXT STEPS
  • Study the derivation and applications of Bernoulli's Equation in fluid mechanics.
  • Learn how to calculate flow rates in different pipe diameters using the continuity equation.
  • Explore practical examples of fluid flow in real-world scenarios, such as plumbing systems.
  • Investigate the effects of pressure changes on fluid velocity and flow rate.
USEFUL FOR

Students in physics or engineering courses, educators teaching fluid dynamics, and professionals involved in hydraulic systems design or analysis.

knightassassin
Messages
13
Reaction score
0

Homework Statement



The figure below shows a stream of water in a steady flow from a kitchen faucet. At the faucet the diameter of the stream is 1.20 cm. The stream fills a 125 cm3 container in 18.2 s. Find the diameter of the stream 13.0 cm below the opening of the faucet. (The answer should be in cm)

Homework Equations


A1v1=A2v2 and P1+0.5densityv^2+density(gh)=P2+0.5(density)v^2+density(gh)


The Attempt at a Solution


Not sure how to attempt this problem. I found the speed at which the water flows
I used the rate (125cm3/18.2)/(0.6^2)pi=6.078 cm/s, but not sure if this information is relevant or not
 
Physics news on Phys.org
This can be done without the Bernoulli equation. Assuming the stream does not break up, the volume flow rate should remain constant. The speed will increase according to simple conservation of energy (potential to kinetic). Actually, that's all Bernoulli's eq is, conservation of energy-per-unit-volume.

After finding the final speed, find the necessary diameter of the stream to provide the same volume flow rate you started with.
 

Similar threads

  • · Replies 16 ·
Replies
16
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 15 ·
Replies
15
Views
11K
Replies
1
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 30 ·
2
Replies
30
Views
3K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 6 ·
Replies
6
Views
3K
  • · Replies 16 ·
Replies
16
Views
3K