Physics debate

[TheMusher]

TBH, I lost a lot of interest after the responses to this post:

viewtopic.php?f=1&t=5438&start=80#p54762

Folks don’t agree with my views (which were really never mine in the first place) on physics? OK. Fine. I can accept that…

Railing against a request for real world data to be collected by an impartial forum member qualified to collect it seems to be something else altogether.

Over to the OP, @Nitram Tocrut to make sense of all this. I can’t.

Dont take it the hard way man! I appreciate you, but have just been trying to tell the data has already been collected. Not sure if the message has gotten through

The data hasn’t been collected. Only the pressure at the binding. That’s the only thing Tom measured.

It is conjecture on anyones part what exact pressure will be on the tip. Why? Because the boot binding pivots on the balance point of the ski. The fulcrum is not under the ski.

Once the pressure on the tip is measured, then the same test should be repeated with a skier in the boot and applying pressure to achieve the same ~3” angle. The pressure reading from that test will then confirm whether, indeed, there is a significant pressure difference imposed by a stiffer flexor when subjected to the pressure of a skier’s foot..

There is no legitimate reason for anyone to waive their hands and say all of this has been done. It hasn’t been done.

You, and others have accused me of relying on theory. When I propose a *complete* practical test, you object to that by preferring to invoke closure based on incomplete information.

I simply don’t understand this behaviour. It is childish and obstructionist, serving no practical purpose. It doesn’t advance knowledge of skiing.

Well mister, afterall you asked for feedback on your proposal, and that was at least my feedback.

I’m sorry if you didn’t appreciate it. It was an attempt to answer your request and expanding the knowledge.

Personally I perceived that you seemed not very receptive to my feedback at all - especially if it didn’t fit your original idea. (Like Stephen say, you kept “dodging”).

Think also after a few days of slamming others physics knowledge (especially in the beginning) while taking the wrong position, it may be advisable to thicken your own skin with respect to the same.

With respect to the dynamics, I’ve been trying to explain why it’s not necessary, but I understand I will get nowhere. I’m not trying to obstruct you from actually doing it..

[GrimSurfer]

I am very receptive to your feedback. Now it’s time to put it all to the ultimate test… full set of measurements.

You seem to think this is about me versus you, others. It isn’t. It’s about getting to the truth. It always has been.

When people say things like “Newtons Laws don’t apply to skiing” or “gravity doesn’t matter in skiing”, what is one left to believe about their level of knowledge?

If I was @Tom M , I wouldn’t touch this subject with a ten foot pole now. The environment has been so utterly poisoned with your animosity, and that of others, that he’s likely going to conclude that he’ll become the community whipping post if he says anything you guys disagree with.

This is the sort of behaviour that utterly stifles any kind of knowledge generation and transfer. The old “holders of the secret fire” shitting on anyone who dare question them when they say things that are profoundly wrong… “gravity doesn’t matter in skiing”.

[Stephen]

If every room I walk into smells like shit, I wonder what’s going on?

Several people have tossed several lifelines, all to no avail.

What hole I’ve dug? I’m standing on a mountain top.


@Stephen is really on the low road here.

[TheMusher]

Think I’m being reminded why discussing physics on www is not always the best idea.

Wish you all a good day/night!

[TheMusher]

You, and others have accused me of relying on theory. When I propose a *complete* practical test, you object to that by preferring to invoke closure based on incomplete information.

This is false. I haven’t criticized you of relying in theory, merely that you’re applying it the wrong way.

I’m not trying to propose you don’t conduct the study. I’m just proposing that if you apply that same law correctly, you could infact derive the answer you’re looking for.

Just an attempt to be helpful.

Anyways, I’m hoping this will be my last post for now.

[GrimSurfer]

You, and others have accused me of relying on theory. When I propose a *complete* practical test, you object to that by preferring to invoke closure based on incomplete information.

This is false. I haven’t criticized you of relying in theory, merely that you’re applying it the wrong way.

I’m not trying to propose you don’t conduct the study. I’m just proposing that if you apply that same law correctly, you could infact derive the answer you’re looking for.

Just an attempt to be helpful.

Anyways, I’m hoping this will be my last post for now.

And what law is that? Hooke’s Law (which doesn’t apply to rubber, which is what the flexor is made of)?

I’ve already explained things according to Newtonian Physics. But I can’t dismiss the opportunities offered by conducting a real world experiment. That is what good science says we should do,

You see, at some point one will need to have quantifiable and repeatable results to prove something. I’m open to the idea that the results could prove Newton wrong… or lowangleal correct. I suspect that the real answer will be slightly more nuanced… like, a firmer flexor will only transmit the force needed to overcome its resistance, and not an erg more.

Such a finding would raise other logical questions, like “if the delta force is only “n”, then what role can a skier play to apply even greater force?”

This is a legitimate question because I can guarantee you that an expert skier on a binding with no flexor or no springs will out-ski a talented amateur 10/10 times. This isn’t magic. And, yes, gravity and Newtonian Physics has something to do with it.

So if we end our questions at that point, one is left with a decision… do I continue on the path of being an equipment hoarder in the hope it will make me a better skier or do I just focus on my skills and get better?”

The answer to this question will determine whether TT folks continue to play “fantasy Asnes gear buyer” on a 24/7 basis (which is kind of what this forum is atm) or pay just a bit more time talking about skills development.

Because when the discussion strays into skills development, there often aren’t a lot of answers given by people who are apparently really good skiers.

https://www.telemarktalk.com/viewtopic ... =80#p54832

The quote above is a good example.

I will wager @lowangle al is an excellent skier. I’m saying that honestly, with out a trace of sarcasm. Yet, he’s at a loss for words explaining how he executes a basic manoeuvre. This doesn’t make him any less good, or any less smart. It just means that, like all of us (and I most definitely include myself in this statement) he’s spent more time doing stuff than thinking about it.

This becomes a problem when it’s time to share knowledge,,which is something that this forum is here to support.

It can’t all be hero shots and boasts of invincibility. I’m neither… is anyone here?

[TheMusher]

And what law is that? Hooke’s Law (which doesn’t apply to rubber, which is what the flexor is made of)?

It’s according to Newtons Third Law:

1) We know the force transmitted through the spring/flexor (Tom M has measured this)
2) We know the vector - ie direction - of the force (diagonally towards the front of the skis)
3) Hence, the normal force (equal and opposite) has to be diagonally in the front of the ski (the ski which obviously is flexible to give a perpendicular surface opposite to the vector, to mount a counterforce).
4) This normal force is what we refer to as tip pressure.

In conclusion, the normal force is in its entirety on the front of the ski - and is therefore known as tip pressure. Same goes for the delta, which is measured to 7 lbs.

If you add weight (skier or otherwise) on the ski, that is just additive (which is not to say total normal force exceeds skiers weight).

Interestingly, you can easily verify this by mounting your boots to a nnn-bc or 75 mm binding, and trying to bend the flexor/75mm sole with the ski. You’ll find it’s only possible pressuring the front of the ski..

[lowangle al]

GS, what was the maneuver I was supposed to explain? I don't have a clue.

[TheMusher]

And what law is that? Hooke’s Law (which doesn’t apply to rubber, which is what the flexor is made of)?

It’s according to Newtons Third Law:

1) We know the force transmitted through the spring/flexor (Tom M has measured this)
2) We know the vector - ie direction - of the force (diagonally towards the front of the skis)
3) Hence, the normal force (equal and opposite) has to be diagonally in the front of the ski (the ski which obviously is flexible to give a perpendicular surface opposite to the vector, to mount a counterforce).
4) This normal force is what we refer to as tip pressure.

In conclusion, the normal force is in its entirety on the front of the ski - and is therefore known as tip pressure. Same goes for the delta, which is measured to 7 lbs.

If you add weight (skier or otherwise) on the ski, that is just additive (which is not to say total normal force exceeds skiers weight).

Interestingly, you can easily verify this by mounting your boots to a nnn-bc or 75 mm binding, and trying to bend the flexor/75mm sole with the ski. You’ll find it’s only possible pressuring the front of the ski..

In layman’s terms:

When you walk, you push the ground.

When you bend the flexor, you push the ground with the front of your ski (not the tail).

[lowangle al]

And what law is that? Hooke’s Law (which doesn’t apply to rubber, which is what the flexor is made of)?

It’s according to Newtons Third Law:

1) We know the force transmitted through the spring/flexor (Tom M has measured this)
2) We know the vector - ie direction - of the force (diagonally towards the front of the skis)
3) Hence, the normal force (equal and opposite) has to be diagonally in the front of the ski (the ski which obviously is flexible to give a perpendicular surface opposite to the vector, to mount a counterforce).
4) This normal force is what we refer to as tip pressure.

In conclusion, the normal force is in its entirety on the front of the ski - and is therefore known as tip pressure. Same goes for the delta, which is measured to 7 lbs.

If you add weight (skier or otherwise) on the ski, that is just additive (which is not to say total normal force exceeds skiers weight).

Interestingly, you can easily verify this by mounting your boots to a nnn-bc or 75 mm binding, and trying to bend the flexor/75mm sole with the ski. You’ll find it’s only possible pressuring the front of the ski..

In layman’s terms:

When you walk, you push the ground.

When you bend the flexor, you push the ground with the front of your ski (not the tail).

Amen Brother, Can't argue with that.