[no_mind_golfer]

Jeff,

No offense but.... before you go any further in your study of the golf swing you really need to STOP! and go take a high school level physics class. I'm dead serious.

What you are saying is absolutely laughable. ITS COMPLETELY AND TOTALLY RIDICULOUS. I would be laughing if I weren't crying. No wonder GOLF myths have perpetuated for so long and are so deeply ingrained.

Try the community college or take the online course at the link I've provided BUT DO IT! You need a basic understanding of these really simple physics principles or else you are wasting EVERYONES' (but especially your) time. Its like someone trying to operate having never studied anatomy. Show my profession some respect!

I will not discuss this or any other subject with you any further. I've provided ample evidence and plethora of links that SHOULD DRIVE THESE VERY BASIC PHYSICS REALITIES HOME to you. But no... You either won't read them or don't believe them so what gives? If you can't find the time to learn the basics then STOP ANYWAY... Just a suggestion.

One last try... READ IT http://www.physics.ucla.edu/k-6connection/forwpsa.htm

nmgolfer

You wrote regarding centrieptal force-: "NO it does not require energy! It requires a FORCE (see click here->Centripetal force requirement. Thi s is why we have a variety of words in the lexicon: FORCE WORK ENERGY etc. soforth.... They have different meanings. AGAIN.... SOME FORCES DO NO WORK."

That's nonsense. If a force is operant, then it must be using energy and therefore doing work.

You equate work only with displacement of an object in space. You do not consider it work to keep an object stationary in the face of opposing forces. However, it does require energy to keep an object stationary if there is another force acting to displace that object. For example, if person A is pushing a three foot X three foot diameter block of steel on an ice rink, then it requires energy to move the block against the resistance of the ice. If person B then stands opposite the block and pushes in the opposite direction with the same degree of force as person A is exerting to push it forward, then person B is using energy, and person B is doing work, even though the block of steel is now stationary (not moving, not being displaced).

Therefore, in your example of a person hanging from a jungle gym by his arms, he is doing work even though he is stationary. He is constantly using muscle energy (doing muscle work) to overcome the effect of gravity on his body mass. If he didn't constantly perform that muscular work, gravity would pull his body down to the ground. You wrongly believe that he is only working when he he does chin-ups and pulls his body up.

You sent me to the following website, which demonstrates that a centripetal force must be using energy, and the constant expenditure of energy represents work.

http://www.glenbrook.k12.il.us/GBSSC...ircmot/cf.html


In that first animation, the ball travels in a straight line if there is no force (requiring energy expenditure) to keep it stationary. In the second animation, a block provides a force that keeps the ball stationary - and that represents centripetal force. Any force that is constantly operant requires energy and therefore centripetal force must be performing work. In other words, energy is required to keep the ball stationary (from traveling forward in a straight line) and the restraining force that provides the "energy for restraint" is performing work.

Hopefully, you are wise enough to realise that your car seat belts (or car airbag) will be performing work to keep you from being ejected through the windscreen if you hit another car head-on at 100mph. The work it is performing is to prevent you from becoming an instantaneous human projectile!

Jeff.