Figure
12.1
Many fluids are flowing in this scene. Water from the hose and smoke from the fire are visible flows. Less visible are the flow of air and the flow of fluids on the ground and within the people fighting the fire. Explore all types of flow, such as visible, implied, turbulent, laminar, and so on, present in this scene. Make a list and discuss the relative energies involved in the various flows, including the level of confidence in your estimates. (credit: Andrew Magill, Flickr)
Chapter Outline
12.1
Flow Rate and Its Relation to Velocity
- Calculate flow rate.
- Define units of volume.
- Describe incompressible fluids.
- Explain the consequences of the equation of continuity.
12.2
Bernoulli’s Equation
- Explain the terms in Bernoulli’s equation.
- Explain how Bernoulli’s equation is related to conservation of energy.
- Explain how to derive Bernoulli’s principle from Bernoulli’s equation.
- Calculate with Bernoulli’s principle.
- List some applications of Bernoulli’s principle.
12.3
The Most General Applications of Bernoulli’s Equation
- Calculate using Torricelli’s theorem.
- Calculate power in fluid flow.
12.4
Viscosity and Laminar Flow; Poiseuille’s Law
- Define laminar flow and turbulent flow.
- Explain what viscosity is.
- Calculate flow and resistance with Poiseuille’s law.
- Explain how pressure drops due to resistance.
12.5
The Onset of Turbulence
- Calculate Reynolds number.
- Use the Reynolds number for a system to determine whether it is laminar or turbulent.
12.6
Motion of an Object in a Viscous Fluid
- Calculate the Reynolds number for an object moving through a fluid.
- Explain whether the Reynolds number indicates laminar or turbulent flow.
- Describe the conditions under which an object has a terminal speed.
12.7
Molecular Transport Phenomena: Diffusion, Osmosis, and Related Processes
- Define diffusion, osmosis, dialysis, and active transport.
- Calculate diffusion rates.
We have dealt with many situations in which fluids are static. But by their very definition, fluids flow. Examples come easily—a column of smoke rises from a camp fire, water streams from a fire hose, blood courses through your veins. Why does rising smoke curl and twist? How does a nozzle increase the speed of water emerging from a hose? How does the body regulate blood flow? The physics of fluids in motion—fluid dynamics—allows us to answer these and many other questions.