quote:Originally posted by MizunoJoe
This is what you are "convincing" me with? You say, "The collision between clubface and ball can be treated very conveniently using...". And write some sort of equation. Just how am I to know that's true? Then you do a bunch of substitutions, etc. and declare that, "The above analysis is totally sufficient in itself...". Again, how do I know that? You need to publish your paper so that it can be judged by those who do such things - like that annual Sports Science Conference or whatever it's called.
Then you again bring up C&S. I can speak to that. First, you say that the difference between the stressed shaft test and the hinged shaft test is "negligible". Not if the 2 wood is only hit 220 yds. Even 20 yrs back, tour players were CARRYING 3 woods 250+ yds. I have doubts that the testers had a golf swing that sufficiently compressed the ball to begin with. But in spite of that, the stressed shaft had a distance advantage of 5 yds, which is significant, and even more so if the swing had a bent left wrist through Impact.
However, the most conspicuous statement in your "analysis" is that the hinged clubhead "BARELY BENT BACK AT ALL". That is to say, it DID in fact cushion the weight of the clubhead rather than completely resist it. Since the hinge was just above the clubhead, this is significant. Does Homer make a quantitative claim on the amount of distance gain from not cushioning the ball? Didn't think so!
I suggest that before submitting your paper to a proper review commitee, you use a tour quality swing to redo the C&S testing and include it.
MizunoJoe,
Rest assured mandarin/horton/peter,paul&mary didn't come up with these equations or do any substitutions. He just lifted then (probably) from Jorgensen.
Some of the surefire signs that pretty much prove mandrin/horton/peter,paul&mary is clueless are:
1. Golf ball mass m is set equal to 0.045
grams. The golf ball we all know and love has a mass of 45 grams. This is the kind of typo that is NOT acceptable (at least according to my 8th grade physics teacher back in the ancient times). The reason why mass is usually in
kilograms is that it simplifies unit calculations. I'll bet mandrin didn't know this.
2. We also have 0.250 gram clubhead.
3. And onwards into equations 7 & 8 where mandrin is "modeling" a 112.5 mph driver swing with head weight of 250 grams (he also has the audacity to call this/these realistic value(s). 250 grams is the weight of a 5-iron head. Most of the driver heads in the market are around 200 grams. A true golf Porfessional at work!
At least to me these look like tabulations of a numerically illiterate person - copy something from a book and bull**** the rest.
Mandrin/horton/peter,paul&mary seems to be rather militant about the "fact" that a golfer can't exert force during impact using the shaft. I guess this stems from the fact (see - no quotes) that it is one of the basic tenents of Single Axis golf. Kind of like their licence to flip it 180 yards w/ the driver. Take it away from them and ...
This mandrin wonk science is fun to play with too.
If we apply the mandrin equations to this Cochran & Stobbs 220 yards 2-wood swing we get some really funny results. In order to produce the 5 extra yards the test subject needed to apply 700 Newtons of force into the clubhead during the impact. (Mandrin - prove me wrong, you wonk [
])
This is: Go to impact fix, rest the clubhead against a doorjamb and push. Hard! The clubhead should be pushing the doorjamb w/ a force of 700 N to reproduce the results of Cochran & Stobbs. You can think of this as pushing w/ 70 kgs.
Not only is this beyond human capabilities, a friggen Klingon couldn't do it. Thanks to leverage that 700 Newtons would break all the small bones in your hands - and yet, somehow - this is what Cochran & Stobbs observed? Holy Smoke!
Wonk science indeed!
I guess it is obvious that mandrins contributions should be taken w/ a grain of salt.
fen
Sorry if I'm riding your coat tails and butting into your conversation MizunoJoe, but I could resist it
