I think it’s because the surface of ice is a thin later of water. You know the difference between solids, liquids and gases, right? in a solid the atoms are quite rigid together and don’t move around very much. In liquids the atoms are able to move around each other and so we slip. I could be wrong, just did a quick google search and it looks like scientists have a few ideas about it!
Hey Jarsden – Ice is slippery because its surface can so easily melt to water which provides a pretty effective lubricant. If you are walking or skating on ice the pressure of your shoes or skates is enough to induce temporary melting. This instantly creates a layer of water that makes it easy to slide.
But if the temperature is too low (below -40°C or so) it is less slippy because it’s too cold for even temporary melting.
Its slippery because of a very thin layer of melted water on the surface. If you get really cold ice, it isn’t slippy at all. You can make this thin layer by putting pressure on ice, the more pressure the more it melts, so a sharp ice skate can cause a little layer of water on teh ice, and the skate slides.
I think the answer is that when we press down on ice it melts a little and the thin layer of water between the ice and whatever is pressing down reduces the friction between the two surfaces. If the ice was very dry and cold, I don’t think it would be so slippery, but it would still be pretty slippery as it tends to be very flat and smooth.