Why is the ice slippery?

A question that science has not found an answer for a century and a half. It is still known that the thin layer of water on the ice surface causes this slippery. But the problem is why ice - unlike most other solids - has that surface layer.

Fluid flow makes it difficult to walk around, even if the water is very thin.

Scientists have long argued that because water has an unusual characteristic of being in a solid state, it has a smaller density than when it is liquid (less dense), so when the pressure increases, the melting point Its will decrease (i.e., ice will melt easily in cold weather, without the need for high temperatures). However, even if this is true, even the tip of the ice skate tip, with very strong pressure, has not melted the ice around it. The hypothesis of pressure is still unconvincing unless the ice sheet is already hot. There is another reason here.

Some studies suggest that friction between skates or tires creates the heat needed to melt ice below. But if the shoes don't move at all? A second hypothesis is that ice already has a liquid layer, stemming from the movement of molecules on the surface because there is nothing to cling to, so it has to move around in search of stability. Slippery characteristics can be a combination of both hypotheses.

Figure skating (Photo: skatetoday)

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