# Fluids

Student Learning Objectives
Lessons / Lecture Notes
Important Equations
Example Problems
Applets and Animations
Videos

Student Learning Objectives

• To understand the concept of mass density.
• To understand pressure in static fluids and gases.
• To use Archimede's Principle to understand bouyancy.
• To use an ideal-fluid model to study fluid flow.
• To understand Bernoulli's Equation and its application.

Lessons / Lecture Notes

PY105 Notes from Boston University (algebra-based):

Introductory physics notes from University of Winnipeg (algebra-based):

HyperPhysics (calculus-based)

PHY2048 notes from Florida Atlantic University (calculus-based):

General Physics I notes from ETSU (calculus-based)

Important Equations

Example Problems

Problem 1
Crew members attempt to escape from a damaged submarine 100.0 m below the surface. What force must be applied to a pop-out hatch, which is 1.25 m by 0.600 m, to push it out at that depth? Assume that the air inside the submarine is at atmospheric pressure and that the density of the ocean water is 1025 kg/m3. (Solutions)

Problem 2
A paperweight, when weighed in air, has a weight of w = 6.90 N. When completely immersed in water, however, it has a weight of win water = 4.30 N. Find the density of the paperweight. (Solutions)

Applets and Animations
 Brownian Motion This applet demonstrates Brownian motion. the big particle can be considered as a dust particle while the smaller particles can be considered as molecules of a gas. Balloons and Buoyancy Experiment with a helium balloon, a hot air balloon, or a rigid sphere filled with different gases. Discover what makes some balloons float and others sink.

Videos

 Download video (3.1 Mb) Watch Streaming Video of Brownian motion. See the animation below for an explanation. Download video (0.2 Mb) Watch Streaming Animation showing the concept behind Brownian motion. The red dots represent water molecules which are too small to be seen with the naked eye. The only thing we can see is the motion of the blue dot which appears to move on its own. Download video (2.0 Mb) Watch Streaming This video shows just how strong atmospheric pressure is. The difference in pressure between the outside of the tank and the inside of the tank causes it to implode.