Calculating Bubble Velocity and Work in a Fluid Container | Help with Pressure

  • Thread starter Thread starter clipperdude21
  • Start date Start date
  • Tags Tags
    Pressure
Click For Summary
SUMMARY

The discussion focuses on calculating the velocity of an air bubble as it rises to the surface of a fluid container and the work done by the buoyant force. The key equations utilized include the buoyant force formula, Fb = ρf * v * g, and the work done by the buoyant force, Work = Fb * H. The velocity of the bubble can be determined using the conservation of energy principle, equating the work done to the kinetic energy of the bubble, where the mass of the bubble is given by ρa * v. This leads to a definitive method for calculating both the bubble's velocity and the work performed by the buoyant force.

PREREQUISITES
  • Understanding of buoyant force and Archimedes' principle
  • Familiarity with basic kinematics and equations of motion
  • Knowledge of fluid density concepts, specifically ρf and ρa
  • Basic principles of conservation of energy in physics
NEXT STEPS
  • Study the derivation of Archimedes' principle and its applications
  • Learn about the relationship between buoyant force and fluid density
  • Explore kinematic equations in greater detail, particularly in fluid dynamics
  • Investigate conservation of energy principles in different physical systems
USEFUL FOR

Students and professionals in physics, particularly those focusing on fluid dynamics, as well as engineers and researchers working with buoyancy and fluid mechanics.

clipperdude21
Messages
48
Reaction score
0
1. A bubble of air of volume v forms at the bottom of a container of fluid (neglect effects of viscosity). Let H be the height of the fluid, and let ρf and ρa denote densities of fluid
and air respectively. How fast is the bubble moving when it reaches the surface?

2. What is the work performed by the buoyant force on the bubble from the moment it
forms on the bottom until it reaches surface?
2. v=vo+at, F=ma, Fb=pvg
3. I have no clue how to solve this. I am assuming it has to do with the equation P(h)= P(O) +pgH and maybe kinematics? For part b i used Fb=pv(of air)g and multiplied it times H so work=pvgH Thanks
 
Last edited:
Physics news on Phys.org
Buoyant force = pf*v*g
Work done by the buoyant force = pf*v*g*H. According to the conservation of energy this work done must be equal to the KE of the bubble. Maas of the bubble = pa*v. Now you can find the velocity of the bubble.
 

Similar threads

Work done on container receiving gas from high pressure container
  • · Replies 1 ·
Replies
1
Views
2K
Is enthalpy just the sum of internal energy and work against external pressure?
  • · Replies 5 ·
Replies
5
Views
1K
Fluid - Work done to blow a soap bubble
  • · Replies 1 ·
Replies
1
Views
3K
The Pressure at the Bottom of a Container
  • · Replies 3 ·
Replies
3
Views
4K
Pressure at the bottom of a container containing two liquids
  • · Replies 6 ·
Replies
6
Views
5K
Need help calculating number of moles
  • · Replies 5 ·
Replies
5
Views
2K
Master Fluid Problems with Bernoulli's Equations | Expert Homework Help
  • · Replies 8 ·
Replies
8
Views
2K
Should I Use the Total Length of an Object to Calculate Buoyancy?
  • · Replies 10 ·
Replies
10
Views
11K
Gas work -- Heating the gas in a cylinder with a weighted piston on top
  • · Replies 13 ·
Replies
13
Views
2K
Fluid static problem with wooden block being pulled down
  • · Replies 9 ·
Replies
9
Views
3K