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PostPosted: Wed Sep 21, 2005 6:55 am 
I think were saying a similar thing to a point :)

Of course I`d include mind intent , and projection as well , and there we`d be forked

Do enjoy your takes on this stuff Jim :)

thanks !! 8)


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 Post subject:
PostPosted: Wed Sep 21, 2005 7:17 am 
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Stryke wrote:
Of course I`d include mind intent


Feel free..

Can you explain it? My focus is generally on one thing only...

BTW:

Just thought of another example... Sneeze vs. Cramp. The guys with the "cramp" have their power "stuck to them"..

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"Receive what comes, stay with what goes, upon loss of contact attack the line" – The Kuen Kuit


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PostPosted: Fri Sep 23, 2005 4:50 am 
Hi Neil:

Rick B is enjoying the discussion and likes that you have a different approach than he does. :D

Here is his latest reply:

A lot of what he says is correct. I believe that he may be over looking that the force applied to an object bringing it to a finite velocity can vary depending upon the how long the force is applied. In other words you can apply a small force for a long time or a large force for a short time. He is correct in that the energy developed is the same but the force applied isn't. The converse applies when you slow an object down. You have to apply the same energy in the opposite direction but the force required will depend upon the time interval that it is applied. A example of this would be to throw a ball of steel and a ball of water of the same mass and velocity into a window. Even though they have the same energy and momentum, the ball of steel would break the glass even at a extremely low velocity. This is because both glass and steel have hard surfaces that don't give. Therefore, when the steel ball hits the window it's velocity is quickly brought to zero, the time it takes (Dt) is very small thus generating a large impact force compared to the ball of water which would take a long time (in comparison to the steel ball) to bring it's velocity to zero.

The force equation (F = M*A = M*Dv/Dt) takes the time interval into account along with mass and the change in velocity, making it a good equation (tool) to explain the concepts or principles required to improve the effectiveness of a strike. Some of the concepts that can be derived.

Mass

The equation describes as the mass increases the greater the force (in our
application) required to absorb the strike. This highlights the need to engage more of our body (mass) in our strikes (connectedness). Stuff like pulling your elbows into Sanchin, shoulders down, engaging the lats, using the hips, expanding (straightening) the rear leg as we punch all connect more mass to the strike resulting in a greater force and energy being developed.

Velocity

Again as velocity of our strike increases, the greater the force (in our
application) required to absorb the strike. What is important in this concept is not the velocity achieved but the velocity dissipated into the object. The force equation clearly shows this as the velocity component is the change in velocity (Dv). Therefore if you were to accelerate a punch to 50 miles an hour and hit an object and you pull it back when it is travelling at 20 miles an hour you would only have dissipated 30 miles an hour in velocity into the object. Therefore V = 50, Dv = 30. This is much less than the potential of 50 miles an hour. This explains the concepts of punching thru an object or time on target. What they are really saying, don't pull your strike. As we have discussed many times I believe that everyone subconsciously pulls their strikes. I am sure that this is a correct concept because we don't do enough damage when we hit each other. Simple calculations of the potential forces developed is huge even with a low velocity and mass.

Note: the force required to pull the punch has to be absorbed by the striker's body. In the case of a punch, if the whole body is not used, it is absorbed into the shoulder/ elbow joints which can cause damage to these joints. This is why I don't punch or kick air.

Time

This is the time interval (Dt) to required to dissipate the velocity (above example 30 mi/ hour). In the force equation, as this time interval is a divisor, the smaller the time interval the greater the force required to absorb the strike. This can easily be understood by punching belly fat or a persons forehead. Which hurts your hand more. When I studied at Neal's dojo, there was a common saying, hard weapon on a soft part a soft weapon on a hard. I think the point of the elbow in the forehead will do more damage than a palm heel.

One consideration of the above is that if one engages all the enablers described, the force that one develops can exceed what the weapon can absorb. This is why we shin kick vs instep kick, elbows vs fists, etc.

Anyway, I still believe that I am using the equation correctly. This is supported by the following example I found on the internet that calculates the impact force generated by a bird impacting an object. In my mind it is the same concept as a fist impacting a human. At the same site it has great examples and explanation of the relationship between force and kinetic energy that may be of interest to your colleague. I tried to use the same numbers ( V=20 mi/hr, weight 10 Lbs, dissipated over 6 " (15.24 cm) in this example as I used for the calculation I did for you many years back. I calc'd 535.8 lb force which matches the attached example. The only difference is terminology not physics, I used the term force and they use Average Impact Force.

Image


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 Post subject:
PostPosted: Sun Sep 25, 2005 6:46 am 
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Posts: 1509
Location: on the path.
I feel like a voice in the wilderness.

The following is a high-school-level summation of Newton's 2nd Law which Rick B has somehow adopted as his latest mis-understood "illumination" of Karate concepts involving power generated by speed, and secondarily promoted by Rick W., who claims to get "lost in the math".
Actually guys, you're "lost in the concepts"which is exactly why you should NOT be using them to "support" your"math"....


"****************
"So what's the big deal? Many people have known Newton's first law since eight grade (or earlier); and if prompted with the first few lines could probably recite the law word for word. And what is so terribly difficult about remembering that F = ma? It seems to be merely a simple algebraic statement for solving story problems. The big deal however is not the ability to recite the first law nor to use the second law to solve problems; but rather the ability to understand their meaning and to believe their implications. While most people know what Newton's laws say, many people do not know what they mean (or simply do not believe what they mean).
Cognitive scientists (scientists who study how people learn) have shown that physics students come into physics class with a set of beliefs which they are unwilling (or not easily willing) to discard despite evidence to the contrary. These beliefs about motion (known as misconceptions) hinder further learning. The task of overcoming misconceptions involves becoming aware of the misconceptions, considering alternative conceptions or explanations, making a personal evaluation of the two competing ideas and adopting a new conception as more reasonable than the previously held-misconception. This process involves self-reflection (to ponder your own belief systems), critical thinking (to analyze the reasonableness of two competing ideas), and evaluation (to select the most reasonable and harmonious model which explains the world of motion).
The most common misconception is one which dates back for ages; it is the idea that sustaining motion requires a continued force. The misconception has already been discussed in a previous lesson, but will now be discussed in more detail. This misconception sticks out its ugly head in a number of different ways (and at a number of different times). As your read through the following discussion, give careful attention to your own belief systems. View physics as a system of thinking about the world rather than information that can be dumped into your brain without evaluating its consistency with your own belief systems.
**********************
Newton's laws declare loudly that a net FORCE (an unbalanced force) CAUSES AN ACCELERATION; the acceleration is in the same direction as the net force." (end of quote.) CAUSES AN ACCELERATION.

---------------------------------------------------------------

Hello, Rick B. and Rick W. : did you read that last sentence, from an online physics HIGH SCHOOL website?

A FORCE CAUSES AN ACCELERATION.
A FORCE CAUSES AN ACCELERATION.
A FORCE CAUSES AN ACCELERATION.
A FORCE CAUSES AN ACCELERATION.
A FORCE CAUSES AN ACCELERATION.
A FORCE CAUSES AN ACCELERATION.
A FORCE CAUSES AN ACCELELATION.


F=ma does NOT calculate the"DELIVERY of the force", it calculates the REQUIREMENT of force to accelerate the MASS.
***************************************

Edited out my incredibly frustrated response to this incredible "toast-rises-because-it's hot" issue.

If this GRADE -SCHOOL explanation cannot clarify it, then I am at a loss.


All I have to add, is: READ THE BOOKS and LEARN what they are saying, don't pervert physics to your own mis-interpreted agenda.

You might want to refer to the above capitilized sentence, repeated to avoid confusion,

A FORCE CAUSES AN ACELERATION.

NM

_________________
The music spoke to me. I felt compelled to answer.


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 Post subject:
PostPosted: Sun Sep 25, 2005 7:38 am 
“The following is a high-school-level summation of Newton's 2nd Law which Rick B has somehow adopted as his latest mis-understood "illumination" of Karate concepts involving power generated by speed, and secondarily promoted by Rick W., who claims to get "lost in the math".

Actually guys, you're "lost in the concepts"which is exactly why you should NOT be using them to "support" your"math"....”



Not lost at all.

The illumination is there for those who have the capacity to grasp it.

No misunderstanding here at all.

I know this because I will compare our striking power with anyone’s – will you?

Please read the concept explained again and this time relate them to striking – which is the entire point – nothing missed here.

As for your dismissive comments about “get and book and read”, Rick B (an engineer) ran his misunderstood use of these theories by six other engineers at his work and all agreed his use of the formula will would work for his purpose. (They have, by the way, read a book or two on the subject.)

THE PURPOSE IS TO HIT HARDER.

You Sir are missing the point.

The use of the equation is to explain how to hit harder.

If you have read Rick B’s explanations and have a concept of how to hit then you can easily apply it to how to hit harder.

You missed the point and frankly I don’t think you will ever get it.

And thanks for the shot about the math, I follow the grade school stuff just fine thank you, it is when Rick B (not you) gets past the level being discussed here that he loses me.

I can follow easily how to translate what Rick B says directly into striking and the actual body mechanics used in striking.

I can prove it works on the dojo floor – guess what – that is good enough for me.

You on the other hand have NOT shown how the explanations we have place here do not work when related in the manner as we have to hitting.

You say it is the wrong formula (so, read the purpose again please) Rick B can prove the “use” of the formula will calculate out just as he has done.

We can show on the dojo floor how the explanations translate directly to different manners of striking. We can show on the dojo floor how the use the formula has been put to work just find for a practical end.

FOR A PRACTICAL END.

Again, I have no issue whatsoever entering the conditioning circle with anyone and comparing their striking methodologies based on their theories with our striking methodologies based on our theories.

The proof is in the practical use of theories. We can apply ours.

The bottom-line is that we are not going to agree with you Neil because our purpose is to hit harder and yours is not, so you will never agree with us.

Perhaps you could post a video clip of you striking and show us where we are wrong.

Here is Rick B. misusing his theories:

http://www.wilsonkarate.com/videos/rick ... _seuka.wmv


I have no issue with disagreement HOWEVER:

Warning:

If you cannot write a response without insults then either take this to the hideaway or cease posting.


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 Post subject:
PostPosted: Sun Sep 25, 2005 2:13 pm 
Quote:
I feel like a voice in the wilderness
Well I'd feel like something if I read a highschool book on physics and then started trying to teach physics to an engineer who is very well respected internationally in his field. But hey what does he know, he's lucky he's got you to lead him from the darkness. How he's managed to feed the family all these years without your grasp of physics Neil is nothing short of incredible. :splat:

I humbly request you stop teaching physics to Rick B, He hits like a tank already if he starts hitting any harder I'm afraid he may kill one of us. :multi: :multi: :multi:


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 Post subject:
PostPosted: Sun Sep 25, 2005 2:16 pm 
Push on a parked transit bus neil, then get back to me and tell us how much acceleration your force created. :?: did you miss something :?: maybe thats in book 2


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PostPosted: Sun Sep 25, 2005 3:52 pm 
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Let m(t) be the mass as a function of time t and let v(t) be the velocity as a function of time t, then the momentum as a
function of time t is p(t) = m(t)*v(t). Further let ' represent one derivative with respect to time, i.e. the instantaneous time
rate of chang of a quantity, then

F1 + F2 + ... + Fn = p'(t) = [m(t)*v(t)] ' = m'(t)*v(t) + v'(t)*m(t) [by the product rule for derivatives]

This form of Newton's 2nd Law is needed to compute the force, for example, on a rocket whose total mass is changing
because it is burning its onboard fuel. So, to describe the force on a constant mass m (or the acceleration produced by a
force on the constant mass m) the simplified version is:

F = m*v'(t) = m*a(t), where the acceleration (the instantanteous time rate of change of the velocity) is a(t) = v'(t).

If we take the (over simplified) example of the 1-dim motion of an object in the gravitational field of the earth (e.g. hold
your pencil up over the floor and then release it) then the acceleration is also constant, i.e. a(t) = -9.8 m/s^2.

However, the acceleration can also increase and a familiar example is driving your car.

Case 1. a(t) = 0
Suppose you are driving your car down the street at a constant rate v(t) = 30 mi/hr, and so your acceleration a(t) = 0.

Case 2. a(t) = c (constant number) != 0
Now, suppose you enter a zone in which the speed limit is 40 mi/hr, and you uniformly press down on the accelerator
producing a constant, nonzero acceleration which gradually and uniformly increases you velocity to 40 mi/hr.

Case 3. a(t) = nonconstant function of time
Now, a key thing to notice for our striking application is that the acceleration may be itself increasing and this occurs when
"punch it" into passing gear, that is, instead of uniformly pressing down on the accelerator, you floor it. In this situation you
experience what is called the "jerk" and that is a nonzero time rate of change of the acceleration itself.

Summarizing, if s(t) is the position as a function of time t, then

v(t) = s'(t), the velocity function, i.e. the instantanteous time rate of change of the position
a(t) = v'(t), the acceleration function, i.e. the instantanteous time rate of change of the velocity
j(t) = a'(t), the jerk function, i.e. the instantanteous time rate of change of the acceleration

F = m*a(t), if we look at this simplified case of Newton's 2nd Law in which the jerk is nonzero and positive, then that
means that the time rate of change of the acceleration is positive, and hence in this case the acceleration is increasing,
which means that the force is increasing, when the jerk is nonzero and positive. This is the interesting case that applies to
the striking situation.

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John

I am always doing that which I cannot do, in order that
I may learn how to do it. Pablo Picasso


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PostPosted: Sun Sep 25, 2005 4:10 pm 
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I think what I get from Neil is that the formula f=ma <although I remember something like this f=ma^2 being used too> is a closer match in proving the storage of force in a mass as velocity and not to prove impact force. Like this:

f=m\frac{dv}{dt}

for a time interval dt.

There are small details in how the formula are applied that can make the difference in passing tests or not in class, something I found out a long time ago, but it's been a long time since Physics.

Pretty much everyone here agrees, I think, that you need to align, you need to accelerate your mass :lol: and you need to do it in a short period of time for short power STORAGE ;) and then RELEASE..on IMPACT.

BTW: The way I teach now to try to explain this very classical training.. Air punching <for our thrusts> in addition to hitting "things" is important for the following reasons:

δ To get the muscles biceps, etc to loosen up and stretch for striking

δ To train flow in chaining strikes together <in forms>

δ To make missing <a target> as natural <recovery> as hitting <a target>

δ To train snap and correct muscle on/off timing

Of course this is in addition to hitting “stuff”. One interesting training thing here regarding “mind intent” or in Cantonese Yi, is to see if you can apply the same intent and mechanic when hitting nothing or an imaginary target vs. a real target like a hanging piece of paper, or a sand bag.. It can be tough.. :)

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Shaolin
M Y V T K F
"Receive what comes, stay with what goes, upon loss of contact attack the line" – The Kuen Kuit


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 Post subject: Wrong math
PostPosted: Sun Sep 25, 2005 4:55 pm 
You guys should be using Probabilities rather then physics.

E.G. What is the probability that you can actually hit something with 99% of X power you can generate while it's moving at random speed and direction?

ANSWER=NONE! HAH HAH


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 Post subject: Re: Wrong math
PostPosted: Sun Sep 25, 2005 5:32 pm 
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The Bronze Dago wrote:
You guys should be using Probabilities rather then physics.

Actually, they're not mutually exclusive. In fact the subject is physics and is called statistical mechanics. :o

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John

I am always doing that which I cannot do, in order that
I may learn how to do it. Pablo Picasso


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 Post subject: Re: Wrong math
PostPosted: Sun Sep 25, 2005 5:58 pm 
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BTW: John I also thought of the jerk thing but don’t know what it says about the process in terms of the change of the change in acceleration. The short power thing does feel like a jerk done with the whole body though, like the sneeze or hiccup.

The Bronze Dago wrote:
E.G. What is the probability that you can actually hit something with 99% of X power you can generate while it's moving at random speed and direction?


That's why "tracking" is so important in some of these styles. Facing and following are key elements we focus on, by training mechanics that constantly require you to *re-face* his CG <aim>, follow <manage space/distance> and stick <for sensory boost and control>.

You train to essentially track your partner like a missile and also close like a missile, while at the same time the partner works to make you lose your "facing"<aim>. This opposing dynamic, done with contact goes a long way toward developing this attribute as does working power generation, while someone tries to smother your limbs, a hell of a way to train short power alignment and release..

Still the theory is what forms the basis of all these methods and understanding them can help support the learning and application processes.

_________________
Shaolin
M Y V T K F
"Receive what comes, stay with what goes, upon loss of contact attack the line" – The Kuen Kuit


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 Post subject:
PostPosted: Sun Sep 25, 2005 6:16 pm 
So where is that factored into John's math :?:

:wink:

e.g. +/-(.707) or some sinsoidial algorithm X some time constant... I dunno, I don't see anything to that effect in Johns math. It just seems to represent a moment in time that is smaller then what the body can respond too.

I'm a new math student... haven't even had calc 1 yet (next semester) but i've got enough instincts to know that something is missing from that forumla.

Personally, I'd rather see a video demonstration of this power. I say one of us should hang a live goat from a tree and hit it over and over again until it's dead! :D

NOW THATS SCIENCE! :D

by the way, isn't that how karate got it's start anyway? I think I read that in George's book, a prince in india sticking needles in slaves...


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 Post subject:
PostPosted: Sun Sep 25, 2005 6:31 pm 
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Location: on the path.
As Shaolin said:
"I think what I get from Neil is that the formula f=ma <although I remember something like this f=ma^2 being used too> is a closer match in proving the storage of force in a mass as velocity and not to prove impact force. "

...You GOT it man!!!
20 lb, or 100 lb, or whatever, used to accelerate a mass, gets stored in the mass as potential energy and it doesn't matter how long it took it to get up to a given speed. That's what F=ma is used to calculate.

Coming out the other end, getting your energy back out upon impact, another formula is used to get "hitting power".

The one I suggested is K = (1/2)mv2, which reads "Kinetic energy is equal to one-half of the mass times the square of the velocity", in plain terms.

Bear in mind I know that all this theorizing has little to do with the Dojo floor, and I'm aware of that, but if one is going to use a formula to prove a concept, you may as well use the right one, that's all!
It's just a physics point, I'm not saying speed is unimportant in hitting or anything like that.

NM

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 Post subject:
PostPosted: Sun Sep 25, 2005 6:46 pm 
Well I'm a fool :oops: :oops: ......I don't understand physics I can just about get a bottle of beer from the fridge ( that's women's lib for ya :evil: )
but I can't feed myself.that's up to the Mem Sahib, who brings it at regular intervals... and cooks it??..and does other stuff.which is why I love her :D
but to a fool.....you could best illustrate your point by posting a clip...or maybe ask your Sensei to post one, all this physics stuff is bloody Chinese to me :oops:


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