# The Physics of a Vortex

Of course, we all know that physics is awesome - but one thing that
sticks out of childhood memories in our infinite curiosity would be
the bottles of swirling of water, spinning into a vortex as it descends.

Or how about those trails of white behind of a jet's wings as you look
out of the window? What about other vortecies that we can't usually see?
Turns out that an airplane is a perfect example of a whole list of cool
vortecies, though many of these provide hazards to others in the sky.

### Examples:

Trailing Vortex The stream of white trailing from the tip of a jet's wing.
Starting Vortex A vortex left behind of an accelerating air foil.
Vortex rings Toroidal vortices are the doughnut shapes in smoke rings.

### Applied concepts

Helmholtz describes motion of vortecies in inviscid flows. If there
is a vortex within a viscid fluid, it decays due to viscous forces.
Helmholtz's Theorems
Reynold's number is a dimentionless number use to describe
aerodynamic forces, based on the inertial and viscous forces
between the object and the fluid that it is flowing through.
Reynold's Number
Bournolli's equation is used very often for describing lift on an
an airfoil. It also helps us understand how the floight of a jet
creates the vortecies along the wings and at the tip of the wings.
Bernoulli's principle

Bibliography