Solve My Mystery: The Winging Seed Problem

[nariman]

Hello To All...
I'm Having A Problem With An Observation...
In This Observation,If I Release A Maple Seed,It Goes Down In A Rotational Movement.
The Question Is Why?
I Hope That Some One Could Help Me...
Thanx...

 

[HallsofIvy]

Take a look at that Maple seed before you release it! It has one "wing" that looks like one part of a propellor. The seed doesn't fall directly down because air pushes up against that "wing". Because of the slant of the "wing", air also pushes it "to the side" causing it to rotate.

 

[dst]

Interesting. I don't know what causes it to gain angular momentum, but once it's in the rotating phase, the gyroscopic inertia from its spin opposes anything that will try to stop it from rotating. It rotates around a common centre of mass, and that happens to be close to the "seed" part. Regardless, it just works like a monocopter - the lift generated by the rotation of the wing, and the inertia generated by that rotation just keeps it spinning and spinning.

Maybe that changes if it hits terminal velocity?

 

[suolintu]

Another IYPT 2008 question (www.iypt.org).