I could try to explain this my way.
Basically, when the skater goes over the ice, he DOES leave imprints on it. However, the pressure applied by the skates, causes the surface of the ice to melt, thereby deleting any evidence of his skating there.
After the influence of the pressure has worn off, the ice surface is exposed to the cool air again, and hence is able to re-freeze, and hence a new surface, without any tracks is formed.
- ARKADYUTI BANDYOPADHYAY Is this is due to Bernolli's principle?
- Ronit Ray Bernoulli's? I doubt it, I think you're overthinking the entire thing. Let me explain. Imagine you have an ice cube in the tray of your freezer. Take a pencil and scratch it. If you scratch less, you'll see the imprint. This is a disturbance on the surface. Due to low temp, the surface will refreeze, causing the layer to become one whole flat surface rather than a scratch. if you scratch hard enough, you can crack the ice cube. The water formed as a result will freeze all over again, to make a single ice cube. This is an extension of the previous example. So if any law is demonstrated here, I guess it's Pascal's law. A liquid seeks it's own level right? Then the temperature makes it freeze. I answer this with a very limited knowledge of physics, so it may be wrong. You would be better off consulting one of our mentors. But logically speaking, I think this makes sense.