TheDevilAside Posted June 28, 2004 Posted June 28, 2004 I'm so glad I chose to take Bio instead of Physics for next year! "If you're going through hell, keep going." - Sir Winston Churchill
White Warlock Posted June 28, 2004 Author Posted June 28, 2004 And you got member of the month? btw, cute belt there. "When you are able to take the keys from my hand, you will be ready to drive." - Shaolin DMV TestIntro
sAtelitte Posted June 28, 2004 Posted June 28, 2004 I failed my physics exam , how much do you guys ask for lessons??? https://www.shaolin.be
TheDevilAside Posted June 28, 2004 Posted June 28, 2004 lol, you're just jealous "If you're going through hell, keep going." - Sir Winston Churchill
JerryLove Posted June 29, 2004 Posted June 29, 2004 Well, I must chime in here and say that if you're trying to be technically correct, then 'weight' is the wrong term to use. Mass is what you're reallly thinking of, because weight is the resultant Force prescribed by a body's mass times the gravitational acceleration of the earth. And for a given person actually experiementing, "weight" works fine... I don't think we have any astronaughts on this BBS that will be trying in oribt. As to the claim that I misread the intent of the original post... my apologies. I skimmed and was reminded of the "F=M/V" discussion on "how to hit harder".... I assumed. https://www.clearsilat.com
Bretty101 Posted June 30, 2004 Posted June 30, 2004 I love these discussions, It is so tricky to apply physics to martial arts. Especially as Jerry says using newtonion pointal physics. I think the key is speed (or velocity) and how you utilise your body weight (mass). These factors we all agree are important. When applying equations it all gets a little tricky as the amount of weight (or mass) in the strike is so variable, and it's motion can be rotational and/or linear. when you throw a punch what is it's mass on impact? your fist, arm or whole body? It all depends on what and how you utilise it. How is force/power connected to acceleration? The equation F=ma is more acurately expressed as a=F/m. Meaning acceleration and deceleration are the result of a force not vice versa (force a result of acceleration.) I did physics at school and even have an engineering degree (I was never any good at english) I wouldn't even start to look at physics too closely. However on the simple basis that mass and velocity are the key to power. I'll try and strike as fast as i can with my whole body and tense on impact to deliver maximum mass at maximum speed. Bretty
DLopez Posted June 30, 2004 Posted June 30, 2004 The equation F=ma is more acurately expressed as a=F/m. Meaning acceleration and deceleration are the result of a force not vice versa (force a result of acceleration.) Cool! A physics problem!! I say it is entirely possible to view Force as a result of acceleration acting upon a mass. I can readily think of an example where acceleration acts on masses so that a force is the result. In fact, it's the very reason you are sitting in your chair looking at your computer screen. The Earth's gravity is an acceleration, that when it acts on a mass, creates a Force called 'weight'. Without the earth's gravitational acceleration, there is no force, no 'weight'. Ah, the wonders of natural science! As far as the mass invovled in a punch or kick, my thoughts are that there are some punches and kicks where only the mass of your fist or foot that is in play, like a roundhouse kick or spin kick, or a back fist punch. Likewise, there are some punches and kicks where you can put more mass behind them like a straight punch, or front and side kicks. If you're like me, it's hard to generate the same speed with a side kick as I can with a spin kick or roundhouse. The extra mass involved is one reason why (along with the fact that I need to work on my side kicks ). DeanDahn Boh Nim - Black-Brown BeltKuk Sool Won"Dream as if you'll live forever. Live as if you'll die tomorrow." - James Dean
Bretty101 Posted June 30, 2004 Posted June 30, 2004 Erm no... Gravity is in fact a force, (F=GMm/r^2) this force f you feel as f=mg where m is your mass in kg and g is the gravitational constant. (which for earth is 9.81) as f=ma=mg, a is therefore 9.81m/s/s which is the rate at which all objects fall towards earth regardless of weight. Force is not the result of acceleration. de/acceleration is the result of a force. Try and give me another example of a force resulting from an acceleration... An object continues at rest or uniform motion unless an external force is applied. (Newtons 1st law) It's been 5 years since i learnt this stuff. Some more physics stuff that will do your head in: 1 cubic metre of air weighs about 1.02kg, and the sound of a travelling bullet actually reaches you before the bullet does, so you might actually hear it!
Thuggish Posted July 2, 2004 Posted July 2, 2004 okay, here goes: velocity is the same thing as speed, two words same meaning. velocity does not have direction. a vector has direction, as well as velocity (sometimes.) you know, martial arts people always seem so into physics, yet they always mess it up somehow. a broken arm throws no punches
Drunken Monkey Posted July 2, 2004 Posted July 2, 2004 ...i always thought that velocity was a vector.... post count is directly related to how much free time you have, not how intelligent you are."When you have to kill a man it costs nothing to be polite."
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