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About this unit

Atmospheric pressure is like an invisible friend who is always squeezing you with a big hug. Learn more about pressure, buoyant force, and flowing fluid so you can appreciate the sometimes invisible, but crucial, effect they have on us and the world around us.
In these videos and articles you'll learn the definitions of density and specific gravity. You'll also learn the definition of pressure, how it relates to force and area, and how to determine the pressure within a fluid. The difference between absolute and gauge pressure will also be discussed.
In these videos and articles you'll learn how pressure variations cause a buoyant force on a submerged object and how to calculate the value of the buoyant force. You'll also learn the meaning of Archimedes' principle.
Flowing fluids behave different from static fluids. In these videos and articles you'll learn about volume flow rate and the equation of continuity. You'll also learn how Bernoulli's principle and Bernoulli's equation relate the pressure and speed of a flowing fluid. The effects of turbulence and viscosity will also be discussed.
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