[chris (OP)]

What makes an icy surface slippery?

Chris

[Geezer]

What makes an icy surface slippery?

Chris

Ice itself is not slippery. The reduced friction we experience on ice is caused when pressure exerted on the ice melts the ice at the interface between our shoes and the ice to produce water. The water acts as an excellent lubricant between our shoe, or whatever, and the ice.

It's not the same as standing in a puddle of water. In that situation, the water is displaced by our shoe which is then able to produce friction with the underlying surface. When we stand on ice, the pressure applied to the ice produces a continuous flow of water between our shoe and the remaining solid ice.

Ice skates take full advantage of this effect by maximizing the pressure and minimizing the friction with a hard smooth surface.

Also, there are studless snow tires (tyres) that improve traction on ice and snow by using rubber compounds that tend to remove water at the point of contact.

[neilep]

I heard a very clever chappy answer this question on the radio at 3:30am this morning  []

[Karen W.]

I would never have thought to ask that question always assumed it was just the water that made ice slick!

[chris (OP)]

I heard a very clever chappy answer this question on the radio at 3:30am this morning  []

Indeed - I always write down the questions that come in and then I post anything that's not on the forum already. This is on the grounds that if someone was interested enough to phone a radio station for the answer then it's likely that others are wondering the same thing.

Another major benefit is that I get to check my own answers and, better still, find out the answers to the stuff I don't know...!

Chris

[yor_on]

Ice is complicated, you think you have it in your glass and then, the next time you look, it's just gone?

As for water creating the effect helping you 'glide'. Yes and no. Geezer is right in a way, wrong in another according to this article in the The New York Times

[Geezer]

Looks like I was conned!

Thanks Yor_on. I think I'm even more confused than I was before.
We could attempt this experiment.

http://www.fotosearch.com/bigcomp.asp?path=IDX/IDX035/395678.jpg

[yor_on]

Well, how did you find me?
I thought I had buried that one???

Yep