What is the Coriolis Principle?

The mathematician Gustave De Coriolis first described the Coriolis Effect, which is an inertial force experienced by a moving body (or, in our application, a liquid) in a rotating coordinate system.

A familiar example of this effect is the difference in the behavior of a garden hose with and without water flowing through it. In the following demonstration, a length of hose is suspended so that it forms a loop, and made to swing back and forth.

When the water is turned off and there is no flow through the hose, the loop swings evenly:

Observe the difference when water is flowing through the hose:

As the water flows through the moving hose, it experiences the Coriolis force at the rotation points (where the hose is suspended). This energy is transfered to the hose at the entry and exit points, resulting in the twisting motion seen here.

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