#physics riddle
My parents have a garden ornament that contains a "vertical spiral thingy" that can freely[^] rotate. When wine blows, it sometimes rotates clockwise and sometimes counterclockwise. What gives? When it has rotated by 180 deg it should be in the same position as if the wind was blowing in the opposite direction (the cage around it nonwithstanding), so I'd expect it to always rotate in the same direction, or to oscillate.
Some videos: https://photos.app.goo.gl/CQWvBBggW4jXQPKZ9
[^] there might be some weird hysteresis there, because it's basically a wire that slips in a hole
@robryk Hm, maybe an obvious thought, but perhaps it isn’t perfectly vertical?
