Inertial oscillations. Not what you want in a tank…

At some point the angular velocity of our tank was accidentally changed a tiny little bit. That was almost instantly corrected, however we could see the effect for quite some time later: inertial oscillations! All the water in the tank moved in circular motions at half the period of rotation.

You read about inertial oscillations in oceanography all the time, but it was really cool to actually observe them!

Inertial oscillations. Not what you want in a tank…