5 ms·
The faster the rock spins, the less it will curl. Ideal # of rotations is about 2.5 or so.
by vhodges 9y ago
The faster the rock spins, the less it will curl. Ideal # of rotations is about 2.5 or so.
- Nomentatus 9y agoWater is complex; surface tension like effects can happen in thin films of it other than at the surface. At greater speeds, these are reduced so the Magnus effect is reduced.
- deleted 9y ago[deleted]
- randomdata 9y agoSo what allows for directional sweeping to make the rock curl even more than it normally would on its own? 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?
- Nomentatus 9y agoRoughening the surface by sweeping thins the film at many points. Your latter two points are more interesting; flow is unlikely, but directional "surface tension" effects (actually organized Van der Waals forces) are certainly possible, given that water is an asymmetrical molecule (which is why surface tension happens at all.)
- randomdata 9y agoAs a follow up, what causes negative curl (when the rock curls in the opposite direction of rotation)? 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".
- jrs235 9y agoShitty ice. 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.
- randomdata 9y agoThat goes without saying, but what are the exact mechanics? 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.
- jrs235 9y agoThe club I curl at is strictly dedicated curling ice and most curlers there take care and pride in the ice and work to keep it clean and in to condition. But we are also open to introducing people and bringing new curlers in. Sometimes people don't wear ideal clothing. They will wear clothes that is linty/fuzzy. Some lint or fuzz gets in the ice and a slow curled stone goes over a piece in the ice which causes a lot of friction b pulling the stone and causing it to start curling the opposite way. That's what I often see. Another thing that sometimes messed with the ice and can cause negative curl is outside conditions. The building isn't perfectly sealed and there are doors to the exterior 3 feet from the outer sheets. If it's above freezing the warm air seeping in can cause the ice near the doors to be frosty or wet (or even colder than normal and harder to melt from some friction if it's extremely cold outside). Depending on conditions. This can mess with the friction between the ice and stone regardless of spin direction.
- randomdata 9y agoI'm not talking about picking, but more to your last point. However, I'm not sure that that still explains the exact mechanics at play.
- jrs235 9y agoA rock spinning too fast will melt more ice in front of the stones path reducing friction and lubing the ice in front and possibly pulling water over to the inside curl side leading it to fall forward more and catch less on the curl side. P.S. This is just my speculation, not from physics but from being a curler.
- vhodges 9y agoSure no problem, I curl myself :)