It’s really, really not.
And where does the energy go?
The bruising and the skull. Some part into the brain no doubt. But you have to compress the skull to transmit the shock into the brain and that also takes energy.
correct, and the compression of the skull raises the pressure inside the skull which is another adverse affect. Since the skull is a rigid object most of the energy passes through. Consider how easy it is for someone to be knocked out by falling over and striking their head against a solid surface.
Being knocked out by falling over and striking your head against a solid surface is mostly caused by sudden deceleration of the brain, which is exactly the point being argued against you.
But I don’t doubt that you could produce a knockout like you suggest, the brain is sensitive enough and immersed in fluid. The disadvantage is that it’s really difficult to execute well enough during combat, it’s easily blocked and delivers a fraction of the momentum of a one handed punch, because that uses your whole body much more effectively, in terms of both speed and mass.
Also I think you are getting confused with the act of purposefully or instinctively moving away from a blow. True, that will deflect some energy but we’re assuming the head is stationary in both cases.
While there is certainly a sloshing of the brain in a fall there is also the kinetic energy of the blow against the head, much as you would get with a hammer. I’ve come close to being knocked out by a hip check to the chest. It’s amazing what a shock wave can do.
Absolutely. It’s not a good combat maneuver because it leaves you exposed to blows from a trained opponent. I brought this up in post 67. It’s got limited practical use unless your opponent grabs you around the chest from behind while your arms are raised. It’s a great maneuver if you get a first strike to the throat below the adams apple and you want to do some damage. Applied to the jaw you have 2 very painful compound fractures.
You are shifting your argument all over the place. What is the conceptual difference between a hammer and a fist?
Debatable, but that would be going around in circles again.
It seems that I’m the only person in this thread that can speak from experience having had a real life altercation with a monkey. It was a female monkey with a baby and they were sitting across a field from me. I thought they looked cute so moved closer to get a better look. As I approached, the mother got more and more interested in me the nearer I got. I got to about 30 feet away and by then the mother was staring directly at me, giving me her undivided attention.
Suddenly she started running at full speed towards me. I started running at full speed in the opposite direction. After a short chase the monkey gave up and went back to her baby.
So yes there is a chance that the monkey will give up if you run. They don’t actually want to fight you so chasing you off is acceptable to them.
Wow, I thought chimps were like 2ft tall. Where do they keep 165 pounds?
Update - Went to the Zoo today instead. We survived. Thought you’d like to know.
/hijack There were no Chimpanzees at all! Half the place is under renovation. Both the giraffes and the seals, (my two favorites) were closed for renovations. But finally got to see a freaking panda after 42 years and at least 20 visits. It was actually very cool to see it sitting there gnawing a big pile of bamboo. Like a painting had come to life in front of me.
And did you know that a zebras bray is halfway between a Donkey’s hee-haw and the loudest, deepest burp you ever heard? Or maybe a Donkey who has studied Mongolian Throat singing. . . either way it was quite arresting. \hijack
I’m trying to give conceptual examples. People understand what a hammer will do to someone’s head yet apply force with a fist and the idea of transmitting kinetic energy seems completely foreign.
Monkey or chimp? We’re talking about chimps here.
Are Monkeys omnivores? I didn’t think so. ::wanders off to wiki::
ETA:
So no, not really the same thing at all. Still, I wouldn’t want to fight a monkey either.
We all understand you, we all just know that you’re wrong, and wonder why you seem incapable of realizing it.
Since everyone else knows that you’re wrong, and you seem incapable of learning, there’s no one else left to discuss this with, so I’m bowing out.
ok ok so it was a monkey not a chimp. monkey chimp chonkey mink they’re all the same
I’m out too, no point hijacking this thread any further.
Remember kinetic energy and momentum aren’t the same thing. Kinetic energy does not have to be conserved as kinetic energy - it can be converted into other forms such as sound and heat.
If you did your bilateral fist strike on a person wearing a motorcycle helmet, where does the KE go? It certainly doesn’t enter the brain via a shockwave, and it isn’t absorbed in fracture or crush damage of the helmet, which would be unscathed. The energy ends up mostly in your hands, where it is dissipated as heat and possibly as damage. A 50 joule punch is doing pretty well and yet 50 joules converted into heat will raise 100ml of water by only 0.1 deg C. I’m betting the average fist contains more than 100ml of water. Any KE actually transmitted to the helmet elastically deforms the hard carapace, converting KE to stored elastic energy. It is then converted to heat and sound as the carapace rebounds outwards and inwards repeatedly over a fraction of a second.
If you were to punch a brick wall hard enough to break your knuckles, I’m sure you would concede that some of the energy of impact has gone into your hand rather than the wall. I’m not sure why you insist that the impact of fist with skull must transmit KE Newton-cradle-style into the brain. Momentum, yes - your fist has stopped and the momentum therefore has to be transferred to the target since momentum is conserved. But KE no: although your fist has lost all its KE, it DOESN’T have to be transmitted to the target, and certainly not as KE. Note that the bilateral impact you suggest has a net momentum of zero.
Try making a Newton’s cradle out of sandbags, or even just replacing the first ball with a little sandbag, and see how much “shockwave” you get then. (A Newton’s cradle doesn’t really transmit a shockwave - it is an elastic wave. Shockwaves exceed the speed of sound in the medium they travel through.) Fist vs. skull is a semi-elastic deformable missile impacting a hard surface. Try rivetting or nailing with a heavy but soft rubber mallet to appreciate the difference. Your nail still stops the mallet, but far less KE is going into the nail, requiring a lot more effort to drive it home.
A motorcycle helmet consists of a hard outer shell and an energy absorbing inner shell. It is not like a human skull. A sandbag is not like a human skull at all. A fist represents flesh and bone as does the skull. It’s an apples to apples collision of objects. In this case, the knuckles represent a focal point of that energy. Just lightly tapping on your temple with a knuckle demonstrates how little effort it takes to cause pain. This is a fraction of the energy that can be applied to the skull.
How hard (as a percentage of the full force of a normal swing) would a wooden mallet have to be swung to knock someone out if their head is against a wall?
I would argue that the hard outer shell of a helmet is very like a skull, if somewhat more fracture-resistant! And the brain does indeed have an energy-aborbing cushion of liquid between it and the skull wall. The sensitivity of pain receptors in the flesh on the outside of the skull are a poor indicator of the strength and toughness of the bone underlying it. (The temple incidentally is also a vulnerable spot because the bone is thinner there due to an internal groove for a big blood vessel, but that’s an aside.)
But that is irrelevant in any case. Answer your own question - where does the KE go if you performed your manouvre on a crash helmet?
I don’t suggest that a sandbag is like a skull - it’s just a useful thought experiment object to demonstrate that KE doesn’t have to be transferred. The steel balls of a Newton’s cradle are very good at turning KE into elastic energy and then back into KE when they rebound, which is why the KE and momentum pass through the centre balls with hardly any attenuation and end up in the far ball. Most objects won’t do this - with sandbags, momentum and KE will be absorbed by the successive bags and leave them all swinging. I suggest that a clenched fist lies somewhere between a steel ball and a sandbag in elasticity and energy absorption.
I don’t think it is an apples-to-apples collision of objects. A fist is a collection of bones held together by elastic connecting tissue and ligments, with a layer of flesh on the outside. A skull is a hard bone box with a layer of flesh on the outside. Fists deform and wobble like jelly on impact with hard objects - I’ll see if Youtube has any slo-mo images of martial artists breaking boards.
A knuckle punch to the temple is a very dangerous blow and one that might well cause a fracture if accurate enough. It’s one of the few cases where skull fracture may be the hoped-for result of a head punch. In that case I happily concede that the blow would be more effective if the target skull were braced or struck simultaneously from the other side, but knuckle-punching both temples at once doesn’t seem very easy to me.
As to your last question, I guess it depends where you hit but there’s a good chance you could inflict an eventually fatal skull fracture without actually achieving a knockout. In that situation I think you’d have to hit much harder with the head braced to achieve a knockout that otherwise, but we’re getting into data-thin territory.
Not a punch, but quite instructive anyway: