中國武術寸勁殺傷力的物理學解釋

請讀者保持耐心，我保證盡可能少的使用物理學名詞，公式。而且使用的是基礎物理。

我中華拳術，素重速度與力量的短促爆發(fā)。這是有物理學根據(jù)的。

物理學中，衡量動能為,M為質量，而速度V則以乘方作指數(shù)級變動，敏感性與重要性尤大。

如同一顆子彈，質量可說極小，但因速度極快，因而殺傷性極大。

但衡量拳的擊打效果，是否就僅僅看動能就行了呢？就是說，只要拳手的質量（一般而言，拳重不應小于拳手體重）夠大，速度越快，他的殺傷力就越大呢？

當然不是，因為這應該涉及到?jīng)_量的概念。

而古中國武術家們，已經(jīng)從實踐中掌握了這一原理，就如同我們在知道燃燒化學公式之前，已經(jīng)懂得使用火。

所以心意，形意，通臂，等諸拳，甚至槍械等，明示‘勁’‘力’不同。勁，從力從巠，巠本義為水脈，引為路徑，脈理，故勁之本義，即有理法，有路徑之力。又勁音同‘進’，訓詁學以字之音同，其義每不相遠。故勁強調力之‘進入’，‘透入’。要言之，勁字之音形義，已明示其有力之運用方式，法則，門路等因素。

拳到極處，殊途同歸，所以我國諸拳法無不強調拳之沖量效果。最明顯的要屬八極拳。八極發(fā)勁要領講求崩、撼、突擊。崩，如山崩之勢；撼，如撼震山岳；突擊，為用法突然，動作干脆。力貫肩、肘、拳、胯、膝、腳于一體之整，發(fā)力瞬間勁如崩弓，發(fā)如炸雷。

其它通背、形意等拳術，有譬如‘冷彈脆快’，‘彈抖’，‘身似弓手似箭’，‘扎槍如射箭’等說法。甚至就連‘運柔成剛’的太極，亦有‘松’，‘發(fā)功如放箭’之語。舉一例，發(fā)放飛刀，在施加最初作用力后，即如同給一沖力，其后任其自駛。則其力量與深入程度，大于你用同樣力量，手持刀柄所能造成打擊效果。

拳王阿里曾經(jīng)比喻‘出拳要象碰到一塊燒紅的烙鐵’，也是說拳要短促。

其實上述說的都是把沖量最大化。

此外，詠春拳亦以“寸勁”著稱，因據(jù)傳其創(chuàng)始人為女子，力量有限，故短橋窄馬，拳出力止。所謂“寸勁”，即短促爆發(fā)出的力量。簡單說：短促距離，短促時間，爆發(fā)性力量。僅就其物理學特征而言，“寸勁”約略當于力學中的“沖力”。

習柔道與摔跤者皆知：倒地時自身應盡量作曲狀與圓狀接觸地面，而特技人員從高樓跳下，落地時先要順勢翻個跟頭。以作緩沖。再舉一例，同一玻璃杯，落地毯上不碎而落磚石地面立碎，并非全因硬度不同，而在于前者延緩了作用時間，而使得沖量效果增大。拳擊手戴上海綿手套，作用也是沖量原理的運用，否則對拳手造成的傷害未免太大。

因而容易得知：考察徒手格斗對敵人造成傷害可以使用動量的改變，也就是沖量。讓我們簡單的復習一下動量定理：

假設質量為M的被攻擊武士，初始速度為（不管是靜止還是運動速度）,在對手的出拳力量F的擊打下，做勻加速直線運動。t秒之后，速度為v，根據(jù)牛頓第三運動定律F=ma 和加速度公式

A=(v-v0)/t

有

Ft=mv-mv0

因為質量和動量的乘積也就是動量。因此，上邊公式也就是：

Ft=p-p0

而力和作用時間的乘積，被稱作力的沖量。因此上邊公式就是我們在初中時學過的動量定理。它的含義是：物體所受外力與動量的改變相當。

動量定理正適用于研究近身徒手格斗這樣的問題。我們可以暫時把拳手的攻擊力等同于沖力。因為攻擊力作用時間短促，而且隨時間變化，因此我們只能衡量它的平均值。

假設武士甲出拳攻擊武士乙成功命中，我們來考察甲的殺傷力。

以甲為研究對象。假定甲的出拳初始速度為，力量為B，對乙的沖力，也即殺傷力為H，根據(jù)牛頓作用力與反作用力定律，甲受到同樣大的反作用力，方向剛好相反。

考察甲的動量變化：出拳速度，命中目標后，在反作用力下速度為v，動量減小為0.

只考慮水平方向上的受力情況，根據(jù)上面的動量定理：，F(xiàn)t=p-p0列式：

(-H+B)t=mv-mv0

也即：? ? ? (B-H)t=mv-mv0? ⑴

因為v顯而易見為0,所以再變換一下，公式變成：

H=B-m（0-）/t

H=B+m/t? ⑵

因為m*v0/t 顯然為正值，所以H必然大于F。

而且，顯而易見，H和拳手質量m與出拳速度成正比，作用時間t成反比。也就是說：殺傷力的大小，要大于出拳攻擊力，而且拳手質量越大，出拳速度越快，作用在對手身上的時間越短，殺傷力就越大。

讓我們具體舉例說明一下：

現(xiàn)在假設已知拳手甲出拳力度F為500牛頓，攻擊作用時間為t為0.1秒，甲的質量為100公斤，初始拳速為6米/秒，現(xiàn)在問甲的攻擊殺傷力到底有多大？

我們把數(shù)值代入算式（2）為：

（500-H)×0.1=100(0-6)

H=500+6000=6500（N）

因此，拳手甲雖然出拳力量是500牛頓，但其實他的殺傷力是6500牛頓。是他出拳力量的13倍。這是相當驚人的。

還應該指出的是，這樣計算得出的，只是平均殺傷力。而最大殺傷力要比平均值更大。

這解釋了為什么詠春拳為什么強調“寸勁”。而詠春高手李小龍先生的功夫片里，他出拳也完美的闡釋了他的攻擊哲學：簡單，直接，脆快。用最快的速度，最小的作用時間，獲取最大的殺傷效果。

雙截棍的攻擊原理也是如此。這種簡單的武器遠遠比它表面更加具有威脅。

也因如此：衡量徒手格斗殺傷力需要考慮四個因素：

(1)質量

(2)出拳力量

(3)速度

(4)作用時間

第一個因素質量：與重量不同，應該用拳手的密度和體積的乘積衡量 即m=ρν。

而第二個因素：出拳力量，由武士的質量，身體結構，肌肉力量等決定。

第三個因素速度得益于內(nèi)部驅動，練習。而作用時間，則完全由攻擊者有意識掌握。

第四個因素是作用時間。

不需要對函數(shù)H=B+mv0/t 進行求導和微分分析，就容易看出：H直接與F正相關。而對m,v0的變化敏感度幾乎相同，對這兩者的變化牽涉到這二者對t的商。而H對t的變動也相當敏感。這當然還由t本身的取值域（區(qū)間）決定。

此外，簡單提一下：寸拳的出手應當是由意領身，以身使臂，以全身力量迅速集中于一點，在最短時間及最短距離爆發(fā)。而寸勁除刻苦訓練之外，別無他法可以獲得?！肮Ψ颉敝Z義，與“工夫”同音，這已經(jīng)指出武術的道路：投入時間和持續(xù)的練習。

Chinese martial arts inch fresh lethal physics explanation

Please be patient reader, I promise to use as little as possible in physics terms, formulas. And using basic physics.

I am Chinese martial arts, heavy prime rate and short burst strength. It is based on physics.

Physics, measure kinetic energy, M is the mass, and velocity V power for exponential change places, the sensitivity and importance of particularly great.

Like a bullet, the quality can be said is extremely small, but fast, and therefore destruction is enormous.

But to measure the effect of hitting boxing, whether you just look at the kinetic energy on the line it? That is, as long as the quality of boxers (in general, not less than boxers boxing heavy weight) is large enough, the faster, the greater his lethal it?

Of course not, because it should relate to the concept impulse.

The ancient Chinese martial artists who have mastered this principle from practice, just as we know that before burning chemical formula, already know how to use fire.

So mind, shaped Italy, through the arm, and other various boxing, and even firearms, express' fresh 'forces' are different. Jin, from the force from 巠, 巠 original meaning water clock, cited as a path, clock management, so the strength of the original meaning, that hair cut, there is a path of force. And fresh sound with 'enter', exegesis to the sound of the word with its meaning not every phase away. Jin stressed that it is the power of the 'enter', 'penetration of'. Yaoyan Zhi, fresh sound of the word form and meaning, has expressed its strong mode of use, rules, opportunities and other factors.

Fist to extreme, the same thing, so all our various boxing boxing emphasize the amount of effect. The most obvious to the genus Bajiquan. Octupole collapse made fresh emphasis on essentials, shake, assault. Collapse, such as the potential of landslides; shake, shake shock such as mountain; assault for the usage of a sudden, the action altogether. Force penetration shoulder, elbow, fist, hips, knees, feet in the whole one, the force strength as instant collapse bow hair as a clap of thunder.

Other pass back, Xingyi and other martial arts, there is such a 'cold crisp bomb', 'bombs shake', 'body like archers like an arrow,' 'bar gun such as archery' and other phrases. Even the 'soft run into just' Tai Chi, also 'loose', 'fat power such as throw' language of. For example, issuing knife, after application of the initial force, namely as a momentum to which he served as its self-driving. Then the strength and depth of greater than you with the same force, the handle can cause hand combat effectiveness.

Muhammad Ali once metaphor 'punches to hit like a red-hot iron', is said to be short punches.

In fact, the above said are the impulse maximized.

In addition, Wing Chun Yi Yi "inch King" is known, reportedly because its founder was a woman, the power is limited, so the short bridge narrow horse, boxing output only. The so-called "inch King," that is a short burst of power. Simply put: short distances, short time, explosive power. Only in respect of their physical characteristics, the "King inch" rough when in mechanics "momentum."

Learning Judo and wrestling are known: when the composer fell to the ground itself should be shaped with rounded contact with the ground, while stunt jumping from high buildings, first homeopathic turned a somersault landing. To as a buffer. As another example, the same glass, not broken down on the carpet and fell broken masonry floor stand, not entirely because of different hardness, but delayed the effect that the former time, and makes the impulse effect increases. Wear gloves boxer sponge, the principle of action is the impulse to use, otherwise too much damage done boxers.

Therefore easy to learn: study unarmed combat damage on the enemy can use to change the momentum, which is impulse. Let us briefly review what momentum theorem:

Suppose mass M attack warrior, the initial velocity is (whether it is stationary or moving speed), at the opponent's punching power F blows, do uniformly accelerated linear motion. After t seconds, a speed of v, according to Newton's third law of motion and acceleration equation F = ma

A = (v-v0) / t

Have

Ft = mv-mv0

Because the product of mass and momentum is momentum. Therefore, the upper formula is:

Ft = p-p0

The product of the force and effect of time is called the impulse force. So on top of that momentum theorem formula we learned in junior high school. Its meaning is: to change the object of considerable external force and momentum.

Positive momentum theorem applies to research melee unarmed combat this problem. We can attack boxer temporarily equivalent to momentum. Time is short because the attack force, and change over time, so we can only measure its average.

Suppose samurai warrior armor punching attack acetic successful hits, we examine lethal armor.

With armor for the study. A punching assumed initial speed, strength is B, for B's momentum, that is lethal to H, according to Newton's law of action and reaction, methyl subject to the same large reaction force, the opposite direction.

A study of the change in momentum: hand speed, hit the target after, in reaction velocity v, momentum is reduced to zero.

Consider only the forces in the horizontal direction, according to the above momentum theorem:, Ft = p-p0-row:

(-H + B) t = mv-mv0

That is: (B-H) t = mv-mv0 ⑴

Obviously because v is 0, so then transform it, the formula becomes:

H = B-m (0 -) / t

H = B + m / t ⑵

Since m * v0 / t obviously positive, so H must be greater than F.

Moreover, it is obvious, is proportional to the mass m H and boxers punching speed and action time t is inversely proportional. In other words: the size of the lethal, greater than the punch attack, and the greater quality boxer, punches faster, the role of the shorter time in the opponent's body, the greater lethality.

Let us explain a specific example:

Now suppose that A is known boxers punching strength F 500 Newton, attack time was t of 0.1 seconds, the quality of armor to 100 kg, the initial boxing speed of 6 m / s, now ask A lethal attack in the end how much?

We value substituted into equation (2):

(500-H) × 0.1 = 100 (0-6)

H = 500 + 6000 = 6500 (N)

Therefore, although A boxer punching power is 500 Newton, but in fact he's lethality is 6500 Newton. His punching power is 13 times. This is quite amazing.

It should also be noted that this calculated, but the average lethal. The average value greater than the maximum lethality.

This explains why Wing Chun Why emphasize "inch fresh." And Wing Chun martial arts master Bruce Lee, he punches too perfect interpretation of his philosophy attacks: simple, direct, crisp fast. With the fastest speed, the minimum duration of action, for maximum killing effect.

Attacks nunchaku as well. This simple weapon is far more threatening than its surface.

Because of this: a measure of unarmed combat lethality need to consider four factors:

(1) Quality

(2) punching power

(3) Speed

(4) duration of action

The first factor of quality: with different weight should be measured by the boxers that is the product of density and volume m = ρν.

The second factor: punching power, determined by the quality of the samurai, the body structure, muscle strength and so on.

The third factor speed thanks to an internal drive, exercise. The role of time, is completely conscious grasp by an attacker.

The fourth factor is the role of time.

Do not need to function H = B + mv0 / t were derivative and differential analysis, it is easy to see: H direct positive correlation with F. While m, change the sensitivity v0 almost the same, these two changes involve both the providers of t. The changes to the H t is quite sensitive. This course is taken by the t range itself (section) decision.

In addition, brief mention: inch punch shots should be led by the Italian body to the arm body to body strength quickly focus on one point, in the shortest time and shortest distance outbreak. In addition to hard training and strength-inch outside, no law can be obtained him. "Kung Fu" of semantics, and "time" are homonyms, which has pointed the way of martial arts: to invest time and duration of exercise.