Bernoulli's Principle
It’s a key idea in fluid dynamics named after Daniel Bernoulli.
In simple terms:
For a fluid flowing smoothly, an increase in the fluid’s speed happens at the same time as a decrease in pressure or a decrease in the fluid’s potential energy.
Where:
- P = pressure in the fluid
- ρ = fluid density
- v = flow velocity
- g = acceleration due to gravity
- h = height above a reference point
Bernoulli's Principle basically says that for a fluid that's flowing smoothly, when its speed goes up, its pressure goes down.
Think of it like this: fast-moving air or water pushes less sideways than slow-moving air or water. The energy in the fluid stays the same overall, but it shifts between motion, pressure, and height.
That's why an airplane wing creates lift. The air moves faster over the curved top of the wing than underneath, so the pressure on top is lower. The higher pressure below pushes the wing up.