Ice is remarkably slippery, but why? Even after more than 150 years of research, the physics behind this everyday phenomenon has remained surprisingly difficult to explain.
Researchers at the University of Amsterdam have uncovered an important piece of the puzzle: highly mobile water molecules at the surface of ice allow objects to slide with very little friction.
What did we discover?
Temperature matters. As ice gets colder, surface molecules become less mobile, increasing friction.
Pressure changes friction. Higher local contact pressure can make sliding more difficult, helping explain why polished skates perform better.
Speed plays a role. The interplay between temperature, pressure, and sliding speed determines how easily a skate glides over ice.
The perfect skating conditions
The research helps explain why ice skating rinks often aim for temperatures around −7°C, where the balance between surface mobility and ice hardness creates favourable skating conditions.
Explore the research
→ Scientific publication: Liefferink et al., Friction on Ice: How Temperature, Pressure and Speed Control the Slipperiness of Ice, Physical Review X (2021)
→ Related research: The Slipperiness of Ice Explained — University of Amsterdam (2018)
Contact: Bart Weber — b.weber@uva.nl