Question
Explain, why no tracks are left on the ice during ice skating?

Answer

The weight of the body acts on a very small area of skate, in comparison to that of ice. Under this high pressure, ice melts to form water below 0°C. The water so formed makes the surface water skating more slippery. But as soon as the skater moves further, the water does not experience any pressure and re-freezes into ice leaving no track on ice surface.

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