Physics debate

[GrimSurfer]

Control, in this context, is the ability to facilitate (or assist) the skier’s movement. It is the skier’s movement that is responsible for the application of mass to the ski.

The skier’s primary control mechanism is the musculoskeletal system. A boot/binding is the secondary control system. A cable is a tertiary control system.

[DG99]

It sounds like you’re making the point that the force ultimately comes from the skiers muscles or weighting, rather than the binding. Since the binding, or the cables specifically, don’t move of their own volition.

??

[GrimSurfer]

It sounds like you’re making the point that the force ultimately comes from the skiers muscles or weighting, rather than the binding. Since the binding, or the cables specifically, don’t move of their own volition.

??

On a very basic level, yes... though I would point out that free will (volition) has no role to play in a physics discussion.

I’d elaborate by saying that a cable *connected to itself*, through a binding, can not deliver any *additional force* because that would violate a law of physics.

None of this is my idea. It started with Isaac Newton. He gets the credit.

[lowangle al]

If Isaac Newton skied, he'd be telling you that cables create force. He'd probably wonder if you were dropped on your head.

[GrimSurfer]

If Isaac Newton skied, he'd be telling you that cables create force. He'd probably wonder if you were dropped on your head.

Al… your arguments are nothing more than conjecture (Newton skiing etc.) and insults (me being dropped on my head).

Surely, you’re able to form better counter arguments than these?

[lowangle al]

I think you have demonstrated a great enough interest in cable bindings to warrant getting a pair to try for yourself.

[GrimSurfer]

I think you have demonstrated a great enough interest in cable bindings to warrant getting a pair to try for yourself.

My original post simply stated that the way some folks think NN 3 pin 75 mm cable bindings work isn’t the way they actually work (if the laws of physics are right, which they invariably are in such cases).

If you feel offended by this, write your congressman or declare jihad on the Royal Society. You could even protest outside the National Academy of Science.

[mca80]

The real question is just how good could Sir Isaac turn?

[GrimSurfer]

Recognizing the role that cables play in the NN 3 pin 75mm binding can open skiers’ minds to the whole of the skier-ski interface.

For instance if cables are needed, then are the boots being used have some kind of deficiency (like too much flexibility)? This was a point @fisheater observed elsewhere.

https://www.telemarktalk.com/viewtopic.php?f=1&t=5501

Or is the issue the skier (in which case a cable system could be used as a training aid rather than an end goal… or a necessary piece of gear in some very unique conditions)?

Reflections on these issues are no different than asking questions on *if* or *why* you need to change flexors. It is not “judging” a 3 pin configuration… it is simply understanding its function better.

But if people can’t accurately explain how cables work (or don’t work), then the only recourse is whether or not to accept popular doctrine. This doesn’t, in and of itself, make anyone a better skier. It just makes people unnecessarily dependent on another piece of gear or equipment.

[leon]

This is a really fascinating discussion. Not sure if it will help my skiing, but perhaps expand my background knowledge of mechanics.

I am not a physicist, but I tried to follow along as best as I could. There were a few mentions of free-body diagrams by @GrimSurfer I believe, maybe others as well. Perhaps one of the physics-inclined members, or @GrimSurfer himself, can draw and post the free-body diagram of forces at play. I think it would really summarize the discussion well and perhaps give everyone a visual representation of the forces and dynamics between the snow surface, ski, binding, boot, and body.