If you stand on ice without moving, no friction exists to generate heat , yet the ice is still slippery. You may ask yourself, can you learn to ice skate on your own. In short,,,,,,,, yes you can learn to ice skate on your own. You will however, have a limit of how much you can learn. Yet, why is it you can skate on ice and not on glass? The water formed makes the skates slide easily over the ice, reducing friction. So, when you are skating, you're skating on a thin film of water, which acts like lubricating oil.
The 25 greatest figure skaters of all time 1 of Brian Boitano. Kurt Browning. Richard Button. Patrick Chan. John Curry. Artur Dmitriev. Peggy Fleming. This push is caused by the ground. Since forces are always an interaction between two objects every force is paired with a second force that is going in the opposite direction. Imagine you are standing with skates on ice and are pushing off of your friend.
The action was more gliding than skating, since the bone blades slid on top of the ice rather than cutting into it. In the 13th century, the Dutch invented skating as we know it by designing skates with sharpened steel blades. For the most part, modern skates have retained this design. At the very heart of skating is, of course, ice. The main theory explaining why ice is slippery, allowing skates to glide along its surface, is more than a century old, but physicists have recently started to refute it.
The blade then glides on the thin layer of water, which refreezes as soon as the blade passes. As the skater gains speed this relative velocity changes.
Consequently, there is a maximum speed a skater can reach, which is directly influenced by how fast he can move his feet on the ice. It can be much more than this if the skater, when pushing off the ice, moves his leg backward with a sideways component of velocity. Analyzing the physics to determine the maximum speed involves looking at the biomechanics of the skater.
To maintain his balance when accelerating forward, a skater will crouch or bend forward in the direction of motion. This prevents him from falling tipping backwards due to the torque caused by the forward component of the force F. By crouching or bending forward, the skater is moving his center of mass forward which creates a counter-torque.
This counter-torque balances the torque caused by the forward component of F , and this prevents him from falling tipping backwards. Crouching or bending forward also reduces a skater's air resistance drag by reducing his frontal area. This allows him to accelerate to, and maintain, a greater speed. In the sport of speed skating, skaters use clapskates which hinge at the front. This allows the blade to remain flattened against the ice when the skater raises his heel, during the stride.
This increases the time that the skater can push off against the ice, which enables him to accelerate faster. At least this is my intuition perhaps completely wrong. Add a comment. Active Oldest Votes. Improve this answer. Compressing a surface of water-ice will melt some surface, but compressing the surface of other materials will solidify any surface liquid, because liquid ice has a smaller volume.
The explanation is fundamentally correct, the bulk melting is irrelevant. I would think at least some of the weight of the skater would be borne by liquid water unless the compressed water liquified, reshaped itself to a lower-pressure configuration, and refroze. Would skis be effective at on a polished frozen sheet of ice? My point is that even if there wouldn't be enough pressure for ice to melt if weight were uniformly applied on a skate, some areas under a skate will usually be under much higher pressure than others.
Bert Barrois Bert Barrois 2, 5 5 silver badges 18 18 bronze badges. References Calderon, C. Reports on Progress in Physics,58, Gwyn Gwyn 7 7 bronze badges. Great to see that there's still new material being published on these topics. Thank you for sharing the paper. It's been bugging scientists and engineers since the 19th century, don't know if this is the final word, but I haven't seen anything new on the topic over the last year or so. Georg Georg 6, 20 20 silver badges 34 34 bronze badges.
Why would you expect skiing and skating to exploit the same mechanism? Why would you expect snow and solid ice to have the same properties?
Johan Johan 11 1 1 bronze badge. Fawad Fawad 4 4 silver badges 18 18 bronze badges. Unless you can prove otherwise I think it is unwise to cite that wikipedia entry as a source.
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