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zoobyshoe
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zoobyshoe said:
Borek said:You don't have to stand on the ice to cut it, just use some large, soft floaters.
Not that I suspect they are artificial.
http://www.poolfloatsmart.com/foam-pool-floats/?gclid=CPjz-5aSi7sCFZeVfgodfi0ArQBorek said:You don't have to stand on the ice to cut it, just use some large, soft floaters.
Not that I suspect they are artificial.
In the original link it was suggested that a bunch of ice debris gets caught in an eddy current with an edge of ice around it. The debris would gradually freeze together while being ground against the edge ice, eventually forming a very nice circle.tiny-tim said:i suppose they can form wherever there's an eddy upstream of a fragile block of ice…
if the sideways pressure is enough to break off a piece of ice on the upstream side of a larger piece, then it won't be able to get past, and the eddy that broke it off will make it rotate
then it'll be like grinding a lens … the edges of both the broken piece and the original piece will (very gradually) be ground down into matching circles
Like a remotely controlled small vehicle?Borek said:You don't have to stand on the ice to cut it, just use some large, soft floaters.
I can imagine that they can form naturally. But I can also imagine a pot of water atoms jumping out of a pot, all at the same time...Not that I suspect they are artificial.
OmCheeto said:Someone posted a video of one of those a few years ago. I have trouble believing they are natural. ...
OmCheeto said:Bamm! Found it! (Ok. That was about 7 hours ago. It was a slow day at work. Please don't tell my boss I was doing science. Please...)
https://www.physicsforums.com/showthread.php?p=2983612#post2983612
The lab experiment was linked to in an earlier post of his:OmCheeto said:Though in Dave's post's, he never posted a reference to the "lab experiment" that recreated this phenomena.
zoobyshoe said:A person could lie on their belly on an inflatable pool raft, yes. This would spread their weight out over a much larger area than their foot prints. Still, the cut disk would have to be thick and strong enough not to break under their weight. Personally, I wouldn't want to mess with river ice, which is going to be much less predictably uniform than pond or lake ice.
If the ice breaks, you don't have a nice circle.Borek said:I think you have missed the point. If the floater is large enough (imagine you are in the pontoon on the ice) you don't care whether the ice breaks or melts. You will be still floating after that.
Borek said:But you don't have to start with an ideal circle, all you need is a rotating sheet of ice. Once it rotates, it will grind itself into a circle.
A rotating ice disk is a natural phenomenon that occurs when a large circular piece of ice forms on the surface of a river and begins to rotate due to the movement of the water.
The size of a rotating ice disk can vary, but they can grow up to 50 feet in diameter, as seen in the recent case of the ice disk formed in a Maine river.
A rotating ice disk forms when the temperature drops and the surface of a river begins to freeze. As the water moves, it pushes the ice towards the edges, forming a circular shape. The rotation is caused by the flow of the water and the shape of the riverbed.
No, rotating ice disks are not typically dangerous. They are a natural occurrence and do not pose a threat to people or wildlife. However, caution should be taken when walking on or near the ice disk, as it can be slippery and unstable.
The lifespan of a rotating ice disk can vary depending on the weather and the flow of the river. Some may only last a few days, while others can persist for several weeks. Eventually, they will melt and break apart as the temperature rises and the water flow changes.