In the 1700s, Daniel Bernoulli investigated the forces present in a moving fluid. This slide shows one of many forms of Bernoulli's equation. The equation appears in many physics, fluid mechanics, and airplane textbooks. The equation states that the static pressure ps in the flow plus the dynamic pressure, one half of the density r times the velocity V squared, is equal to a constant throughout the flow. We call this constant the total pressure pt of the flow.

As discussed on the gas properties page, there are two ways to look at a fluid; from the large, macro scale properties of the fluid that we can measure, and from the small, micro scale of the molecular motion and interaction. On this page, we will consider Bernoulli's equation from both standpoints