What is the relationship between pressure and fluid dynamics in this problem?

AI Thread Summary
The discussion centers on applying Bernoulli's equation to analyze the relationship between pressure and fluid dynamics in a specific problem involving fluid flow from a bottle. It suggests treating the speed of the water inside the bottle as negligible and the gauge pressure outside the nozzle as zero. The height of the water inside the bottle is considered as "-h," while the height of the nozzle is adjusted to "+h" for clarity in calculations. The work done on the liquid is described as P ΔV, which is necessary for lifting the fluid and providing kinetic energy to the stream. Understanding these relationships is crucial for solving the problem accurately.
willworkforfood
Messages
54
Reaction score
0
http://portfolio.iu.edu/whoblitz/problem.png
I think Bernoulli's equation is involved in solving this problem, but past that I'm not sure what the pressure of the water inside would be or what it would be outside. Any advice appreciated, as always.
 
Last edited by a moderator:
Physics news on Phys.org
Treat the speed of the water inside the bottle as "zero." Treat the gauge pressure outside the nozzle as zero. Treat the water level inside the bottle as "-h." Go Bernoulli.

Edit: Wait, you are solving for the gauge pressure inside the bottle, so it would be more direct to have the height of the nozzle as "+h." It comes to the same thing.

The speed of the fluid inside the bottle is not exactly zero, but it is so small (and the squared value makes it smaller) that it is safe to "call" it zero.
 
Last edited:
The work done on the liquid is P \Delta V and is required to lift the fluid through the height h and impart kinetic energy to the stream.
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
Thread 'Correct statement about a reservoir with an outlet pipe'
The answer to this question is statements (ii) and (iv) are correct. (i) This is FALSE because the speed of water in the tap is greater than speed at the water surface (ii) I don't even understand this statement. What does the "seal" part have to do with water flowing out? Won't the water still flow out through the tap until the tank is empty whether the reservoir is sealed or not? (iii) In my opinion, this statement would be correct. Increasing the gravitational potential energy of the...
Thread 'A bead-mass oscillatory system problem'
I can't figure out how to find the velocity of the particle at 37 degrees. Basically the bead moves with velocity towards right let's call it v1. The particle moves with some velocity v2. In frame of the bead, the particle is performing circular motion. So v of particle wrt bead would be perpendicular to the string. But how would I find the velocity of particle in ground frame? I tried using vectors to figure it out and the angle is coming out to be extremely long. One equation is by work...
Back
Top