Have you ever wondered how ice skaters roll ?? something to do with the ice being slippery perhaps ?!
Suprisely, it's not simple as you might think and the exact mechanism behind how ice skaters actually work has been wholly disputed for years ..
- One theory is the heat generated by the friction of skaters moving on the ice, This sound logical but it doesn't explain why skaters still slippery even at stand still !
- Anothor theory is the pressure of the skaters wight applied through the narrow metal plates that reduces the melting point of the ice and again produces a slippery film to ride on.
and it is true, pressure can reduce the melting point of ice as this experiment will demonstrate :
* Bring block of ice around which a wire is surrounding and is attached to some wights.
* Watch and wait .. The wire will start to cut in the ice block* As the wire passes through, the ice above it will refreze !! and the block will still very very solid.
Unfortunately, this pressure theory doesn't provide the hole answer either. A typical skater only produces enough pressure to reduce the ice melting point by few degrees which would make skating at any thing just below zero a bit tricky.
So, what's the answer ??
Well, the latest scientific thinking is that there is a combination of the pressure theory and friction theory along with the fact that the bonds that bond the ice molecules together are weaker near the surface .
All together produce a slippery film needed for ice skating ;) ;)
