Key result: viscosity spikes + thicker film (~100–500 nm)

23:22of the slimy water. Yes. that we talked about earlier on on its face. Uh water is not very viscous. >> Uh you know it it which allows it to in the tree example float up >> uh because it's not introducing uh new friction. >> Yeah, it's very slippery. >> It's very slippery. >> Uh which means it can move around very easily. >> In order for skating, ice skating to work in the way we think about it. At a minimum, the top layer of the big body of ice >> needs to be extremely viscous. Exactly. >> Uh meaning not slippery, meaning be able to being able to catch onto basically grab onto the blade >> as it's moving on top of the surface.

24:03And this is the first indication that where we can measure and see that oh actually that top layer is highly >> highly viscous. And if you were to now calculate how thick would the fil the film be? >> Yes. >> It's now 100 to 500 nanometers >> instead of just a couple. >> Yeah. It's like two orders of magnitude above what we thought it should be before. And so now that layer is enough, >> right, to to >> to lubricate this contact between >> my blade and the ice >> and the ice, >> right? And this was this was in 2019. It was it was I thought it was a really cool experiment just the way that they constructed an AFM, which is pretty established now, but they attached it to this tuning fork to get that XY

24:45>> displacement as well. I I just want to briefly note this is a very interesting point about how when tools are built AFM crisper etc etc tools or let's say platforms however you want to categorize it >> they're not uh in a finite state of completion >> no >> right you can add your aftermarket attachments >> on top of it >> for different use cases and this is a perfect example of taking AFM and having a little additional attachment on there that allows you to see stuff a little bit differently that's very cool >> yeah yeah it's it's very cool And and the other thing that they could tell from this new technology is like not only why is it viscous, they could also tell that the reason why that thing was viscous is because there's tiny little

25:26ice crystals >> Mhm. >> in that layer of water that's causing the viscosity to go up. >> Interesting. >> Right. And that's what makes sense. So now when it comes to like, you know, why do we why do we put wax on our on our coating? Like when we do skis and stuff like that, I mean the at the Olympics, everyone's waxing their skis, right? And the reason why you want to wax your skis is because they're hydrophobic. They they don't like water on it, right? And that's actually enhancing this viscous property of that layer, >> which is which is kind of cool. It's like kind of >> it's making that >> more scientifically justified. Before it was just like an observation. It's like,

26:07hey, if I wax like it just works. and people had handwavy ideas, right? But now we're really getting into the physics of it. It's very very cool. Okay.