Ripping Sound of Skates

[Triinkii]

I have always been curious of this, but does anyone actually know the physics of that "ripping" or "crunching" sound of blades on the ice when high-level skaters do edges?

I hear it spoken of as a good thing to achieve, as it means you have weight on the edge/power in the push, but also isn't it inefficient for the kinetic energy to have turned into sound?

Can definitely confirm I have physically been able to create that sound, and either feel that strong push and gain speed  , but also in some cases I have been able to hear the sound and be slow and gain no power from the push  . Perhaps those were two completely different physics principles happening.

Looking forward to hearing all your thoughts

[Bill_S]

It's not an analysis, but a series of observations follow.

I presume that the crunch sound is of ice yielding. The blade is wedging the ice away from it's original location. The stronger the push, the deeper the groove left behind. The displaced ice is the source of snow on the surface.

From an energy standpoint, the sound produced as well as the non-elastic deformation of the ice must reduce power available to the skater. That's engineering dynamics. Anecdotally I can skate with the most perceived speed and power a few minutes after an ice cut. The somewhat softer ice is quieter and my blade doesn't slip with a strong push. I feel faster and in better control. Harder ice seems to produce more noise from pushes, and my blades slip sideways more. Larger amounts of slip become disconcerting, especially when my blades are loaded with cornering forces in addition to stroking pushes. That's the limit.

Hockey players can really tear up the ice during strong cornering accompanied by a great racket. The ice damage is very visible and is one cause of a figure skater's lament.

BTW, have you ever heard a high-pitched "screeeee" when your blade placement on the ice is too flat? The blade skidding is huge, and you're close to a fall. Thankfully, I don't hear that sound very often.

Anyway, those were a few thoughts that came about your questions.

[tstop4me]

No physics discussion, but here's an interesting discussion of skating sounds by a figure skater:

https://www.npr.org/templates/story/story.php?storyId=6550604

[Note:  There is an accompanying audio clip.  Click the white triangular play button (on a blue circular background) to the left of the title "Hearing a Smooth Skate on the Ice".]

[nicklaszlo]

I have always been curious of this, but does anyone actually know the physics of that "ripping" or "crunching" sound of blades on the ice when high-level skaters do edges?

I believe the answer is no; much is not understood about the mechanical properties of ice.

I hear it spoken of as a good thing to achieve, as it means you have weight on the edge/power in the push, but also isn't it inefficient for the kinetic energy to have turned into sound?

You are right.  Power causes the sound.  The sound does not cause power.

[tstop4me]

I hear it spoken of as a good thing to achieve, as it means you have weight on the edge/power in the push, but also isn't it inefficient for the kinetic energy to have turned into sound?

Theoretically, mechanical energy that is converted to sound energy is wasted.  But of course there's the question of how much energy is thus wasted.  I don't have an estimate, but I have a feeling it's not significant.