- #1
jumpjack
- 223
- 3
Take a look at these videos:
Smoke rings in air:
http://www.swisseduc.ch/stromboli/etna/etna00/etna0005video2-it.html?id=14
Air rings in water:
http://www.youtube.com/watch?v=bT-fctr32pE&feature=related
Second one is really amazing, as it shows two things:
- great stability of the ring, which prevents air from escaping the ring itself for a long time
- possibility to "extract" a ring from another
I wonder how it is possible. I think some strange physics law apply here, where "strange" means something like the law which makes a spinning top have the axial precession, and which prevents a giroscope from being rotated perpendicularly to its rotation axis.
If you look at "dolphin rings", you can see that, when a ring is cut, two things happen:
-The dolphin bends a part of the rings, just like if it was a solid thing, and brings the edge of the cut to touch a part of the ring; this makes the edge "join" to the ring, thus creating a secondary ring.
-The remaining part of the old big ring remains alive for a bit, moving toward dolphin body, and it eventually disappears.
I think air particles have two combined movements: a rotation around the "ring axis" (a "circular axis" actually), and a rotation around the axis perpendicular to ring's plane.
I'll try to draw a picture...
Smoke rings in air:
http://www.swisseduc.ch/stromboli/etna/etna00/etna0005video2-it.html?id=14
Air rings in water:
http://www.youtube.com/watch?v=bT-fctr32pE&feature=related
Second one is really amazing, as it shows two things:
- great stability of the ring, which prevents air from escaping the ring itself for a long time
- possibility to "extract" a ring from another
I wonder how it is possible. I think some strange physics law apply here, where "strange" means something like the law which makes a spinning top have the axial precession, and which prevents a giroscope from being rotated perpendicularly to its rotation axis.
If you look at "dolphin rings", you can see that, when a ring is cut, two things happen:
-The dolphin bends a part of the rings, just like if it was a solid thing, and brings the edge of the cut to touch a part of the ring; this makes the edge "join" to the ring, thus creating a secondary ring.
-The remaining part of the old big ring remains alive for a bit, moving toward dolphin body, and it eventually disappears.
I think air particles have two combined movements: a rotation around the "ring axis" (a "circular axis" actually), and a rotation around the axis perpendicular to ring's plane.
I'll try to draw a picture...
Last edited: