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# How fast do you ski? - Page 8

I got the Ski Tracks app late last season. Hit 47 mph last March, 48 mph in December, and 54 mph in January.  I've now stopped turning it on when I ski -- I now have a sense of my top speed, have no desire to ski faster, and don't need an app getting my competitive juices flowing to see if I can go a bit faster.

Faster than some..slower than some...

Quote:
Originally Posted by Pierre

Lately I have been working on achieving higher edge angles, slower overall speeds and lower max g forces for the same size turn and slope than I previously was capable of pulling off.  Most skiers think my turns are mostly rail road tracks but my turns are not even close to being RR track turns.  RR track turns are pretty boring in my opinion.

It's physically impossible to achieve higher edge angles and lower g's at the same time. The only way to achieve higher edge angles is to move your center of mass closer to the center of the turn and the g's (centrifugal force) are what keeps you from fallling over. The higher the edge angle the more g's it takes to keep from falling over. Actually you have it backwards. Edge angle serves the turn, not visa versa. The point of achieving higher edge angles is so you can make a tighter turn at higher speed. The formula is  a=v (squared)/r, where a is angular acceleration=centrifugal force=g's (different units, same concept).

I was bombing a groomer on tuesday. Wearing sunglasses and a pom beanie. Without the goggle strap to hold it on, I was having issues with the hat blowing off at top speed.

true story.

if you want to see  fast head over to Sun Peaks March 11-14 for the Velocity Challenge.

Only FIS speed skiing event in N America. Current mens top speed is a bit over 178Kmh thats about 111 MPH.

A friend often placed first or second in ladies event.

My buddies and I think we can ski fast but trying to keep up with her even without the speed suit was a reality check.

Quote:
Originally Posted by oldgoat

It's physically impossible to achieve higher edge angles and lower g's at the same time. The only way to achieve higher edge angles is to move your center of mass closer to the center of the turn and the g's (centrifugal force) are what keeps you from fallling over. The higher the edge angle the more g's it takes to keep from falling over. Actually you have it backwards. Edge angle serves the turn, not visa versa. The point of achieving higher edge angles is so you can make a tighter turn at higher speed. The formula is  a=v (squared)/r, where a is angular acceleration=centrifugal force=g's (different units, same concept).

I am not attempting to violate physics. We don't ski in a Newtonian world.  By changing DIRT, we have momentum, gravity and slope we can play with.

Your statement appears to assume near perfect carving.  We also do not necessarily need to move the CM inside for higher edge angles.  That is what angulation is all about.

Quote:
Originally Posted by Pierre

Quote:
Originally Posted by oldgoat

It's physically impossible to achieve higher edge angles and lower g's at the same time. The only way to achieve higher edge angles is to move your center of mass closer to the center of the turn and the g's (centrifugal force) are what keeps you from fallling over. The higher the edge angle the more g's it takes to keep from falling over. Actually you have it backwards. Edge angle serves the turn, not visa versa. The point of achieving higher edge angles is so you can make a tighter turn at higher speed. The formula is  a=v (squared)/r, where a is angular acceleration=centrifugal force=g's (different units, same concept).

I am not attempting to violate physics. We don't ski in a Newtonian world.  By changing DIRT, we have momentum, gravity and slope we can play with.

Your statement appears to assume near perfect carving.  We also do not necessarily need to move the CM inside for higher edge angles.  That is what angulation is all about.

Angulation can only move the COM so much, after that you have to pull more G's to stay upright. And obviously on a steep slope you can maintain a high edge angle relative to the slope in the last part of the turn as you cross the fall line, even if you're not carving, but not through the entire turn, unless you pull the G's. One reason carving is important is that once you start to skid a turn you lose angular momentum (ie G's) and flop over if your COM is too inside. On a steep slope as you skid the tails to set the edges to kill speed you have to move the COM down hill at the same time.

We all ski in a Newtonian world, except Ghost who apparently approaches the speed of light.

I laughed - OldG ! Say again - Pierre   everything you see or do is governed by Newtonian Mechanics..And OldG Touche, only a 'Ghost' can conceivably approach the speed of light, and that is still governed by Newtonian Mechanics

Edited by dustyfog - 3/6/15 at 10:16am
Quote:
Originally Posted by dustyfog

I laughed - OldG ! Say again - Pierre   everything you see or do is governed by Newtonian Mechanics..And OldG Touche, only a 'Ghost' can conceivably approach the speed of light, and that is still governed by Newtonian Mechanics

Approaching the speed of light is or even a high rate of speed is also controlled by Relativity; E=MC2. As speed increases and the amount of energy being put into an object so does mass and it takes more energy to add speed to the larger mass. Also mass can not go as fast as light. This works in particle accelerators they actually add mass to particles as they speed them up, so when the hit the target there is more mass to make a trace.
The only time the laws of physics can be broken is when beer flows in the bar and so does the BS. Joke there guys.

Ok, Tom - E=MC^2 is just the key equation for General Relativity. The derived conclusions include: Mass -> Infinity as Velocity->speed of light in the limit. Point is it's not Quantum Mechanics, the mechanics are still Newtonian.

buddy of mine always skis down faster than me, he is always waiting for me at the lift. I dont ski very fast IMO.

We went and did 3-4 runs on the NASTAR course...i smoked him every run. (my skis were even quite a bit wider than his)

The next day he decided to work on his turns.

Edited by WC68 - 3/6/15 at 4:27pm

The empiric proof of the theory of relativity can be found in the expansion of time--the way the last 5 minutes of a close basketball game takes 45 minutes.

That equation is for special relativity, not general. Now if I could ski moguls, that would be really special.

Does time ever move differently for you?

I know definitely two things that travel faster than light - BS & rumors.

Quote:
Originally Posted by dustyfog

Ok, Tom - E=MC^2 is just the key equation for General Relativity. The derived conclusions include: Mass -> Infinity as Velocity->speed of light in the limit. Point is it's not Quantum Mechanics, the mechanics are still Newtonian.

All the things I said will happen as you go closer to the speed of light.
I only talked about quantum mechanics as it shows the relationship of energy and mass.
Even at this small of a change in spped this was the result; two very accurate watches were synchronized one stayed still and the other was flown in a very fast jet, when they were brought back together the fast one was behind the still one in time.
The orbits of the planets never matched Newtonian physics until Relativity, when relativity was plugged into the orbital calculations the math worked out right on. E=MC2 is this Energy = mass x the speed of light squared.
Therefore E *1/M=C2 and therefore 1/M=1/E*c2 and therefore M=E*1/c2 or M=E/Mc2. Of course this is just the basics of it, it gets much deeper. Relativity works at all speeds and gravity masses, The measured differences show up the most when you have a high energy mass compared to a low energy mass.
Edited by tomfifield - 3/7/15 at 3:34am
Quote:
Originally Posted by oldgoat

The empiric proof of the theory of relativity can be found in the expansion of time--the way the last 5 minutes of a close basketball game takes 45 minutes.

Or in the dentist chair.
This is all fun, but getting back to reality of what the forces on a real world skier are, we can round off the math and drop the effect of Relativity as the relativistic speeds are so close that it is negotiable, for this Newtonian physics works fine; especially when considering the variables such as the correlation of frictions involved. I do not have any of my Physics books with me so I will just have to think of the top of my head.
Some of the factors involved would be; acceleration ant that would be( Vf-Vi/T) this would be a function of Newton’s law of gravitational acceleration whereas ( V=32’ per sec sec) minus the angular velocity (how steep the slope is) as a vector and minus the correlation of friction between the skis and the snow with the mass to surface area of the body in relation to the altitude and air thickness, then factor in the surface condition of the clothing being worn. So at any given moment speed would be a derivative of time in comparison to acceleration and deceleration.
This would be for someone straight lining down the slope, if the are making turns the math just got a lot more complex.
Edited by tomfifield - 3/7/15 at 3:31am

I always get a chuckle when I see folks referencing their speed from gps units.

Quote:
Originally Posted by tomfifield

Quote:
Originally Posted by oldgoat

The empiric proof of the theory of relativity can be found in the expansion of time--the way the last 5 minutes of a close basketball game takes 45 minutes.

Or in the dentist chair.

I post on TGR.

I am a dentist.

ES: correct Special Relativity .
Tom: phenomenon of time dilation has nothing to do directly with the speed of light
Theory of Relativity : Special and General are not directly related to Quantum Mechnanics .
The mechanics here are Newtonian 3 laws.
Dental dance in a mouth is governed by Newton's laws but the drill could rattle a few protons loose.
Oldg: now that is great analogy.
Relativity works on anything with mass, no matter what the speed it is going. Yes I know relativity and quantum mechanics are not the same although there are some links. Thereis no working grand unification theory yet, gravity on a quantum level is not understood for one.
I may not be an expert at this but I have read a number of books on the subjects, and taken a number of classes in physics in collage, and engendering as well, so I do not think I am all that dumb on the way it works.
I have to admit I read the actual math formulas for Relativity and it was way above my understanding.

I have said nothing that this simple explanation does not say. Read #7 to 9.
http://www.space.com/28738-einstein-theory-of-relativity-explained-infgraphic.html
Edited by tomfifield - 3/8/15 at 3:12am
Quote:
Originally Posted by tomfifield

Relativity works on anything with mass, no matter what the speed it is going. Yes I know relativity and quantum mechanics are not the same although there are some links. Thereis no working grand unification theory yet, gravity on a quantum level is not understood for one.
I may not be an expert at this but I have read a number of books on the subjects, and taken a number of classes in physics in collage, and engendering as well, so I do not think I am all that dumb on the way it works.
I have to admit I read the actual math formulas for Relativity and it was way above my understanding.

I have said nothing that this simple explanation does not say. Read #7 to 9.
http://www.space.com/28738-einstein-theory-of-relativity-explained-infgraphic.html

Don't feel bad, the math was a little hard for Albert too; that's why he got Hendrick to help him.

It's all about time, stubbornly sticking to Isaac's laws is what made Albert think about changing time.  IMVHO Quantum Mechanics is a cheat, but wth, if the theory can explain things and make predictions then it's a good theory.  So....what if we had quantum time?  Could we get to the stars in short order?

Quote:
Originally Posted by Ghost

Don't feel bad, the math was a little hard for Albert too; that's why he got Hendrick to help him.

But he kept mixing up his 6's and 9's..

Science always has doubters. Quiz: what is this a picture of and proof of?

a) Hiroshima. Relativity theory.

b) Los Angeles in 2065. Global climate change.

c) all of the above

Since this thread is pointless, the physics police has made the decision to intervene.

Quote:

Originally Posted by dustyfog

ES: correct Special Relativity .
Tom: phenomenon of time dilation has nothing to do directly with the speed of light
Theory of Relativity : Special and General are not directly related to Quantum Mechnanics .
The mechanics here are Newtonian 3 laws.
Dental dance in a mouth is governed by Newton's laws but the drill could rattle a few protons loose.
Oldg: now that is great analogy.

I guess the sentence in response Tom could be true based upon your "version" of directly. In this case, directly doesn't include the second axiom of special relativity, or any calculations of time intervals from any inertial reference frame...or any calculation really. Then yes, that would be true.
Quote:
Originally Posted by oldgoat

Science always has doubters. Quiz: what is this a picture of and proof of?

a) Hiroshima. Relativity theory.

b) Los Angeles in 2065. Global climate change.

c) all of the above

Something to think about, nuclear bombs are based on a fact of relativity yet what could be more on a quantum level than busting up the atom.
It is about time to argue over skiing fast with or without a helmet.

I think people should be more worried about how much control they have when skiing than how fast one goes. Speed can be fun but only if you are doing it safely and in control.
Edited by tomfifield - 3/9/15 at 5:42am
So, it's not actual speed, but relative speed.
Speed relative to the conditions (both internal and external) and the ability.

Original dry observation was Newtonian mechanics govern what skiers deal with, and of course : Relativity was the great discovery explaining source of 'gravitational force' and a whole host of other things BUT it has little to do with Quantum Mechanics as of yet ... http://phys.columbia.edu/~cqft/physics.htm

Physics Police - you got me spooked : splitting my hairs, ok, ok - good thing I still have a mane  you know what I mean..or someone does...

Cgd: I would think - pictures are (c) ... tragedy unfolding as we speak..except for the ruling majority party in SLC, out west there are few skeptics left... they live it every day..

Tomf: That's a great link..am going to show it to a few people..succinct,  great plain-speak image-laden explanations for those who want it

I don't ski too fast..except when I lose control then it's Newton's Third Law which rules the outcome..

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