ater is a great substance, especially when
it freezes. It becomes slippery and is fun
to skate on. But why is it that ice is so
slippery? It is not because it’s flat. Glass,
for example,is flat but notslippery.What
we need is a layer of water to turn a flat surface into a
slippery one.And sure enough, if we skate on ice we
skate on a thin layer of water