Stands for Conservation of Angular Momentum (I alpha^2) where alpha is angular acceleration.
At the top of the back swing... How much angular momentum is there?
1/3 of the way down.. How much?
Half Way down?
and at impact?
Easy right? At the top there is none... zero... zip... nada. Things are stopped. 1/3 of the way down... There is some.. things have begun to move
1/2 way down... There's even more... now the golfswing is really picking up speed and starting to rotate fast. Finally at impact? Maximum momentum, maximum rotation *that is unless you subscribe to some ignoramus teacher's ridiculous theory of kinetic chain snapping in which case you've probably lurched yourself to a halt and incurred a mishit*
If angular momentum is increasing as the downswing progress' all but the dimmest among us must agree, then by definition angular momentum it is NOT being conserved. (If as time progresses you have more or less of somthing it is NOT being conserved). COAM does not apply to the golfswing and I refer you to any physics or mechanics textbook if you disagree with this definition of COAM.
Dante wrote a pretty good book back in the 60's (5 magic moves). In it he had stroboscopic pictures of one golfer whose hands slowed down before impact (they almost came to a halt in fact). Dante extrapolated from his sample of one (never a good thing to do btw) to all golfers.
Since he did not know how to explain this observation himself, Dante consulted a physics teacher who told him the golfers hands slowed down because of COAM (sounds good in theory.... but wrong ... for the reason given above). Also note the: "Appeals to authority" logical fallacy. He's a physics teacher so he knows right? wrong. Perhaps Dante should have consulted with more experts to confirm the firsts explanation and golf instruction would not be mired in this COAM myth. Hind sight is of course 20-20.
It turns out very few people swing a golf club like Dante's stoboscope model anyway. In fact Nesbit's data shows most golfers (especially the better ones) accelerate their hands all the way to impact. (See figure 4 http://www.motionanalysis.com/pdf/2005_nesbit.pdf ) BTW... Nesbit used the finest "3d machine" available to acquire his measurements. Some people choose to ignore that which does not fit their preconceived notions especially slayers of windmills.
PS
Check out fig. 7 of the linked pdf. That's angular velocity. For those who did not make it to (or forgot) calculus, the slope of that curve is angular acceleration. Note its increasing for all golfers right up to impact. Angular momentum IS NOT being conserved during the golf swing. Have a good day!
No mind golfer,
appear to me you have limited knowledge to the golfswing, what also concerns me is you have never studied biomechanics, so with out measured data how can you make judgment, the body nor the arms continue to speed up in the golf swing. each body segment hits a peak speed and decelerates even the arms, at the point of impact all moving body parts are decelerating hips,shoulders arms and hands.
I think you need to read 2-m-1 to learn and understand conservation of momentum in golf and 2-E
it eludes me how you can past judgment when you have not data or background in golf biomechanics. I know for a fact you haven't cause if you did you would know all body segments accelerate, but before impact are all decelerating Then you would fully understand stand how coam works in the golf swing.
what truth are you presenting, I swear you and jeff are mates , how can you present truth when you have no data or research in how the human body functions in the golf swing. your going off opinion not research or facts here.
The body speeds up this is hilarious
Last edited by biomechanic : 11-01-2008 at 12:01 PM.
Reason: spelling
It appears all you know how to do is toss out insults and try to present yourself as an expert yet there is never any (technical) substance in your posts. Are you insecure? Are you incapable of communicating in a technical manner? Can you for once base an argument on science? The Ad Homenim logical fallacy will not work with me.
Here's what you do... You state exactly what is wrong then explain exactly why it is wrong. Detail your work then maybe a discussion can take place. You should have learned how to communicate in school. You did attend school did you not? I assume you graduated from high school.
Originally Posted by biomechanic
No mind golfer,
appear to me you have limited knowledge to the golfswing, what also concerns me is you have never studied biomechanics, so with out measured data how can you make judgment, the body nor the arms continue to speed up in the golf swing. each body segment hits a peak speed and decelerates even the arms, at the point of impact all moving body parts are decelerating hips,shoulders arms and hands.
I think you need to read 2-m-1 to learn and understand conservation of momentum in golf and 2-E
it eludes me how you can past judgment when you have not data or background in golf biomechanics. I know for a fact you haven't cause if you did you would know all body segments accelerate, but before impact are all decelerating Then you would fully understand stand how coam works in the golf swing.
what truth are you presenting, I swear you and jeff are mates , how can you present truth when you have no data or research in how the human body functions in the golf swing. your going off opinion not research or facts here.
The body speeds up this is hilarious
this is hilarious
Hybrid Mode
