This seems similar to the Magnus effect:
https://en.m.wikipedia.org/wiki/Magnus_effect
(Spinning a pen fast enough can turn it into a wing, causing it to behave strangely when tossed upward)
https://en.m.wikipedia.org/wiki/Magnus_effect
(Spinning a pen fast enough can turn it into a wing, causing it to behave strangely when tossed upward)
And why does the same directional sweeping technique, except applied in reverse, cause the rock to curl less than it normally would on its own?
And why does applying sweeping with both techniques at the same time counteract the directional movement?
Not something you are bound to see in professional level arenas, but not uncommon in clubs.
In fact, what makes club ice seemingly impossible to make behave like arena ice? There is a serious amount of research by Canadian universities that has gone into trying to make club ice act like arena ice for training purposes and the best we have been able to do is "almost the same".
To add: Curling on ice used for other purposes too leads to shitty ice. The ice needs to be flat and level. Zambonis do not lead to level ice. Dual purpose rinks likely also don't shave the ice to ensure level and flatness. Likewise, gouges in the ice from skates causes unpredictability and some might compensate by over pebbling prior to playing. Also poorly/sparsely pebbled I've can lead to unpredictableness.
To your edit:
> Curling on ice used for other purposes too leads to shitty ice
Certainly skating ice is a whole other beast to curl on, but I'm talking about club ice: Ice that is only used for curling.
It seems to be related to uneven cooling of the ice. It really becomes apparent on the southern-most sheet in the club I frequent when the late-winter sun starts beating down on the southern-facing wall next to it, but that is not the only place I have seen it happen.
However, outside of the high level reasons for it happening, I am interested in the specific mechanics, like were previously described for normal curl, that causes the rock to go the opposite way under these conditions.
Of course I'm speculating on the specific underlying cause, but I would be pretty surprised if the mechanic isn't just the rock sliding downhill.
P.S. This is just my speculation, not from physics but from being a curler.
I curl and play pool, so I've come up with reasons for the difference in my head.
The slower turning side creates more friction because it grabs the ice, the faster side glides over rather than grabbing. This is obvious when you intently watch as the curl picks up at the end of the shot.
QED, dunno why a bunch of non-curlers wrote these articles they should just curl.
Don't both sides turn at the same speed?
For surfaces that do not melt to create a liquid film, this intuition is wrong. If any sliding is taking place, then static friction has been overcome, and kinetic friction is at play. Dry surface kinetic friction doesn't increase with speed: well, the coefficient doesn't but the actual force does!
https://physics.stackexchange.com/questions/48534/does-kinet...