“Alpensia” appears like a venue straight out of Frozen, however you gained’t discover any summer-loving snowmen there—simply actually chilly Olympians. The ski resort in Pyeongchang, South Korea is among the coldest ever to host the Winter Video games, and the bitter temperatures have claimed some surprising casualties: skis.
Throughout the lead as much as the video games, athletes and trainers told Reuters’ Peter Rutherford they had been trashing their skis throughout apply runs. The slopes had been so frigid as to render high-tech gear nugatory. However why?
Seems that in the precise temperatures, snowflakes can flip from fluffy sparkles into razor-sharp, ski-destroying spikes. And for downhill skiers, who depend on the physics of friction to zip down the slopes, super-cold snow can spell catastrophe for his or her most necessary equipment.
“At temperatures slightly below freezing, it’s extra like snowboarding on water. However with colder air, it’s extra like snowboarding on sand,” says Kenneth Libbrecht, professor of physics at Caltech and a specialist within the construction of snowflakes.
It might not appear to be it, however speedy skiers are certain to the legal guidelines of physics like the remainder of us. At the same time as their our bodies zip downwards with the assistance of gravity, they face friction that may influence their pace and, in extraordinarily cold temperatures, their skis.
You’d suppose friction would merely gradual skiers down, however it could actually truly make skis glide throughout the snow extra rapidly. Because the skis drag, they soften a small quantity of snow beneath them. This isn’t a results of stress, says Libbrecht, however reasonably of warmth. That melted snow acts like a lubricant and makes the skis slip much more rapidly.
However warmth is simply a part of the story—and physicists aren’t precisely certain how the remainder of the story goes. For years, they’ve debated the precise mechanism of snow, ski, and skate friction. Proper now, the prevailing principle is that ice and snow soften a tiny bit as quickly as they’re shaped, making a quasi-liquid film that will get friction going the second a ski or skate touches them.
That movie acts like a lubricant. Add Olympians’ skis to the combo and also you get much more pace. They’re made from high-tech composite supplies designed to soak up racing wax, which creates extra lube and, hypothetically, even quicker runs.
Sounds speedy, proper? Positive…till issues get actually chilly. “The colder it will get, the tougher it’s to soften that layer of ice,” Libbrecht explains. And when temperatures get under about -15°C (slightly below 16 °F), snowflakes are typically extraordinarily sharp—the equal of tiny, crystalline razors.
“It’s not like a bit of metal slicing by means of you,” he clarifies, however the sharpness of the flakes mixed with the slower soften fee of a chilly day is sufficient to harm skis. What must be a slippery expertise finally ends up being extra like snowboarding over sand, with no layer of lube to guard skis. As a substitute, the chilly, spiky snowflakes harm the gear in a phenomenon referred to as base burn.
Your common skier may attempt for an additional run. However for an Olympian, who could win or lose a race by only a fraction of a second, that’s clearly not an choice.
Olympic athletes present up on the Winter Video games with tons of skis underneath the perfect of circumstances—up to 70 pairs for some opponents. However when it’s as chilly (and spiky) as it’s in Pyeongchang, they may simply want they’d packed a number of extra for good measure.