Foot Pounds, Momentum, Inertia etc...

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Exactly, only momentum is conserved in collisions. The confusion about kinetic energy and momentum within the shooting community is a legacy of mass marketing by inprint gunwriters. For more than a century, Gunwriters have attempted and continue to attempt to make lethality a precise science...
The fact that energy is not necessarily conserved in collisions does not mean that it is less relevant or that momentum is somehow more relevant because it is conserved. One might even argue that the fact that energy can be converted into work in a number of ways is what makes it especially relevant to the topic of terminal ballistics.

It is certainly true that there is a lot of confusion about kinetic energy and momentum, however I don't think we can blame gun writers for that confusion.
The Kinetic energy school has been dominant among gunwriters primarily because it favors velocity.
Actually, had you asked me, I would have said that there are more gun writers who downplay kinetic energy as being an effective measure of terminal effect than there are those who favor it. At any rate, there are certainly gun writers on both sides of the aisle.
This is typical:
It may be a typical advertisement, but it certainly isn't a typical example of gun writers favoring velocity or energy since Weatherby was not a gun writer.
Martin Fackler and other lethality testers came to the conclusion that KE was not a measure of lethality.
I agree. I am of the opinion that there will never be a single number quantity that is an accurate measure of lethality.

However, it is true that kinetic energy is related to the potential of a projectile to do work/cause damage. And that has nothing to do with marketing. The relationship was discovered long before anyone was selling ammunition and long before anyone was marketing firearms based on velocity or energy.

Anyone who believes otherwise, should provide some evidence of which ammunition company Gottfried Leibniz was working for when he discovered kinetic energy in the late 1600s. Or which firearms/ammunition company was funding Emilie du Chatelet's experiments which confirmed the validity of Liebniz's energy theory in the early 1700s. It would also be interesting to know what brand of firearms or ammunition that the Bernoulli brothers and Gravesande were trying to sell.
 
Actually, had you asked me, I would have said that there are more gun writers who downplay kinetic energy as being an effective measure of terminal effect than there are those who favor it. At any rate, there are certainly gun writers on both sides of the aisle.

Mass marketing has to change with the times as do forms of entertainment. Comedy changes, for example, What were once scary monster movies are quite tame by today's standards.

How compelling is this vintage advertisement?

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glowing butter anyone?

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after viewing this, are you energized to kill the Kaiser?

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I still read a good number of KE calculations in gun magazine articles. So as an advertising tool, it is still being used. If there is any lessening of the usage, it probably has more to do with the direction the market is moving. Hunters are dying faster than their game. KE matters little in punching holes in paper. What I see is a movement towards long range ballistics. New cartridges, new bullets, with improved characteristics at 1200 yards. Now in my area, there are very few 1000 yard ranges, where is that list of 2000 yard ranges? And, who is pulling the targets?


It may be a typical advertisement, but it certainly isn't a typical example of gun writers favoring velocity or energy since Weatherby was not a gun writer.

You are right, it is an advertisement, not an article. I encourage anyone to find the articles of yesteryear, and see if there is a pattern to what characteristics were considered quality attributes. I am of the opinion that there are, but of course, mass marketing has to change as the market moves. The great wild cat era was based on velocity, and the numbers we read came from print publications. Chronographs were huge things that few had. Once affordable chronographs came on the market, people found that the actual velocities of their improved cartridges were less than advertised. But, there is no profit to be made refuting old advertising claims, so the impressions stay in the public memory for a long time. How many people still think well of Volkswagen engineers? These guys are so eco virtuous that they sprouted angel wings.

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Probably many believe Volkswagen engineers sit by the right hand of God. Volkswagen is more profitable now than before their Dieselgate problem.

I consider gun writers as shills, taking their talking points from their industry sponsors. Or, think of them as sock puppets, you don't see the hand moving the mouth, but it is there.
 
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That's a lot of stones thrown in a lot of wells--I find I don't have sufficient inclination to try to pull even one out, let alone all of them.
 
If you understand vector calculus than think of work as ft •lb (dot product) and torque as ft x lb (cross product). In the former case the force is parallel to the direction of movement and in the latter thay are perpendicular.

Mike
 
I would humbly suggest that people who don't really know anything about physics let others explain. There are some posts in this thread which, in spite of an effort to salt them with terms that sort of seem like physics, are basically layman guesswork, due to lack of understanding on the parts of the writers.

In situations like this, it's best to let people who have the training speak. You can't fake a knowledge of physics after half an hour of Googling. It's not the same as several years of undergrad and graduate classes or a career as a working scientist. You may fool your beer buddies, but you'll just make trained people cringe.

The link I provided is very good, and it contains material written by someone who actually knows physics. By that I mean someone with real training, not someone who got A's in basic high school or university physics. Best to listen to physicists, ME's, and maybe EE's, who don't work with mechanics a whole lot but are probably the smartest engineers.

https://www.real-world-physics-problems.com/difference-between-momentum-and-kinetic-energy.html

No disrespect intended, but it's disconcerting to see people looking for answers in a cloud of BS that never should have been raised.

As for kinetic energy equaling lethality, I used to think it made sense. Then I read the FBI's report that followed the Miami Shootout, and I decided to go with big, wide bullets in my carry piece. Whether the FBI knows anything about physics, I can't say, but they do have a ton of knowledge about what happens in real shootings. Maybe they're wrong, but I trust their conclusions more than mine.

Ultimately, isn't shot placement the most important thing?
 
Best to listen to physicists, ME's, and maybe EE's, who don't work with mechanics a whole lot but are probably the smartest engineers.

Yes, we should put all of our stock in ivory tower specialists, especially those so enveloped in that world that they will read someone describing something with "/" as "over" or "divided by" instead of considering the context and deducing that it means "or", "alternately".

Suggesting that people should dismiss anyone's input on a particular subject as invalid because that input isn't backed up by a MS or PhD is the epitome of arrogance. If I need to find out how to capture neutrinos, I'll ask one of your ilk. On matters like this, I value the input of someone who has no formal education but a lifetime of experience at least as much as the ME/EE who can put the numbers together in physics terms.
 
Yes, we should put all of our stock in ivory tower specialists, especially those so enveloped in that world that they will read someone describing something with "/" as "over" or "divided by" instead of considering the context and deducing that it means "or", "alternately".

Suggesting that people should dismiss anyone's input on a particular subject as invalid because that input isn't backed up by a MS or PhD is the epitome of arrogance. If I need to find out how to capture neutrinos, I'll ask one of your ilk. On matters like this, I value the input of someone who has no formal education but a lifetime of experience at least as much as the ME/EE who can put the numbers together in physics terms.

As respectfully as I can, after being told I'm arrogant for tactfully stating the obvious, I have to tell you that you don't even know enough about physics to know why you're mistaken. It's extremely clear--indisputable--from what you've written. You would have to take at least two semesters of calculus and two semesters of physics just to get to the point where you could understand a physicist if he told you why you were wrong. Why not listen to people who know the subject?

Physics is science, not something you can learn from your buddies. It's the hardest field of study there is. Math is hard, and getting a math major is a joke compared to getting a physics major. I know; I majored in physics and minored in math. I have enough credits for a math major, but I elected not to take one of the requirements so I could take a different math course of more use to physicists.

You can't pick physics up from common sense or experience. It doesn't work that way! You can't even pick up a really bad and embarrassing understanding of physics without study. Momentum and kinetic energy aren't just phrases anyone can understand. They are scientific terms with strict mathematical definitions. You have to spend a great deal of time in lectures and doing problems to understand what these terms mean.

Your confusing use of bolding makes me wonder if you know what "mechanics" means.
 
There's two things at work here being largely ignored.

F=MA, PLUS the additional inertia provided by the bullet spin, from rifling.

All the physics of bullet motion in the world don't calculate for an animal's reaction to the given ballistics of a given
caliber cartridge. Which makes a lot of the objective math subjective, inasmuch as you are looking for a bullet which
will work for you, with the animal you are hunting, at the distances you are shooting. You can talk physics till dawn, but
IMHO, most of us just want a bullet that's going to drop a given animal with a center mass shot.

No matter how well you can express the ballistic difference between, say, a 180 grain and a 220 grain 30.06 soft tip,
until you use that 220 in the field, in order to support or deny your theoretic supposition, all those #s are merely a proposal.
 
There's two things at work here being largely ignored.

F=MA, PLUS the additional inertia provided by the bullet spin, from rifling.

All the physics of bullet motion in the world don't calculate for an animal's reaction to the given ballistics of a given
caliber cartridge. Which makes a lot of the objective math subjective, inasmuch as you are looking for a bullet which
will work for you, with the animal you are hunting, at the distances you are shooting. You can talk physics till dawn, but
IMHO, most of us just want a bullet that's going to drop a given animal with a center mass shot.

No matter how well you can express the ballistic difference between, say, a 180 grain and a 220 grain 30.06 soft tip,
until you use that 220 in the field, in order to support or deny your theoretic supposition, all those #s are merely a proposal.

My undergraduate degree is in physics. And I would classify myself as a hard-core experimentalist. The writers I like are some you may never have heard about: P O Ackley, and Harold Vaughn for example. So I do have great respect for practical results.

Are you seriously proposing that Ohm's Law, Conservation of Momentum, Boyle's Law, and Kirchoff's Laws are only general approximations that may or may not hold, and of little use? I assure you my friend, it is not so. To be granted the status of physical law, a result has to be replicated many times by many people, and shown over and over to hold.

There are some things in the world that we can model extremely well. Other things are harder. Internal ballistics as a function of pressure and bullet mass are very well understood, and the real world results match the model within our ability to measure. Wounding ballistics is hard. Nobody I know of has a model for that, at least one that I believe. AFAIK, we can grub out some rules of thumb, and that's about it. Hanging your argument on lack of that model is awfully flimsy.

But one of the other posters made my day: Someone here knows about dot and cross products. I mean, damn, there's just one example of someone who obviously did some serious studying in college. And that's far from the only post that shows that level of understanding. I would not scoff at any such. In fact, I would say it is wonderful to enjoy the company of people like that.
 
I do disagree with the conclusions stated in this article:

The Difference Between Momentum And Kinetic Energy

https://www.real-world-physics-problems.com/difference-between-momentum-and-kinetic-energy.html

For two objects having the same momentum you want to be struck by the heavier object since it will inflict less damage.

The example given is a 0.1 kg (1/4 lb) object and a 10 kg (22.5 lb) object, both having the same momentum. The author is correct in saying the KE of the lighter object will be orders of magnitude higher, given the same momentum, but his conclusions of lethality are based on intuition. I would like to see some calculations of object weight, object momentum, and maybe, how much momentum or KE it takes to create a lethal wound. It probably varies depending on the impacted body part.

Now I don't have a lot of OJT killing people, but a 22.5 lb iron ball should positively crack a skull, and it does not have to be moving fast to do this. I have read posts where assailants killed by striking an individual in the head, with a ball hitch held in the palm of a hand. If I searched, somewhere out there someone was killed with a 20 lb circular bar bell weight.

Glad I only play with guns, these fatalities with barbells have convinced me that weight lifting is a dangerous sport!

Man bludgeoned to death with barbell at Bally Total Fitness gym
http://www.latimes.com/local/lanow/la-me-ln-man-killed-barbell-bally-gym-20140919-story.html


Student dies after snapping neck when 315lb weight slipped during bench presses
https://metro.co.uk/2016/12/29/man-...5lb-weight-while-doing-bench-presses-6350658/

Fitness fanatic, 28, found dead under weight-lifting bar 'after trying to lift too much while alone in his garage'
http://www.dailymail.co.uk/news/art...ad-weight-lifting-bar-trying-lift-garage.html

Man dies when 220 pound bench press machine crushes throat
https://nypost.com/2017/11/08/man-dies-when-220-pound-bench-press-machine-crushes-throat/

Teen Dies After Being Crushed By Weights While Bench Pressing
https://www.menshealth.com/fitness/a19537287/teen-ben-shaw-crushed-after-bench-pressing/

Barbell accident kills former UN leader accused of corruption
https://www.theguardian.com/us-news...-kills-former-un-leader-accused-of-corruption
 
I do disagree with the conclusions stated in this article:

The Difference Between Momentum And Kinetic Energy

https://www.real-world-physics-problems.com/difference-between-momentum-and-kinetic-energy.html

For two objects having the same momentum you want to be struck by the heavier object since it will inflict less damage.

The example given is a 0.1 kg (1/4 lb) object and a 10 kg (22.5 lb) object, both having the same momentum. The author is correct in saying the KE of the lighter object will be orders of magnitude higher, given the same momentum, but his conclusions of lethality are based on intuition. I would like to see some calculations of object weight, object momentum, and maybe, how much momentum or KE it takes to create a lethal wound. It probably varies depending on the impacted body part.

Now I don't have a lot of OJT killing people, but a 22.5 lb iron ball should positively crack a skull, and it does not have to be moving fast to do this. I have read posts where assailants killed by striking an individual in the head, with a ball hitch held in the palm of a hand. If I searched, somewhere out there someone was killed with a 20 lb circular bar bell weight.

Glad I only play with guns, these fatalities with barbells have convinced me that weight lifting is a dangerous sport!

Man bludgeoned to death with barbell at Bally Total Fitness gym
http://www.latimes.com/local/lanow/la-me-ln-man-killed-barbell-bally-gym-20140919-story.html


Student dies after snapping neck when 315lb weight slipped during bench presses
https://metro.co.uk/2016/12/29/man-...5lb-weight-while-doing-bench-presses-6350658/

Fitness fanatic, 28, found dead under weight-lifting bar 'after trying to lift too much while alone in his garage'
http://www.dailymail.co.uk/news/art...ad-weight-lifting-bar-trying-lift-garage.html

Man dies when 220 pound bench press machine crushes throat
https://nypost.com/2017/11/08/man-dies-when-220-pound-bench-press-machine-crushes-throat/

Teen Dies After Being Crushed By Weights While Bench Pressing
https://www.menshealth.com/fitness/a19537287/teen-ben-shaw-crushed-after-bench-pressing/

Barbell accident kills former UN leader accused of corruption
https://www.theguardian.com/us-news...-kills-former-un-leader-accused-of-corruption

Yes, there are some problems with the article.

For starters, it speaks of objects having weight in kilograms. Ouch! Kilograms are mass, not weight.

And it is not true that the firearm and the bullet have the same momentum. The correct statement is that for a freely recoiling firearm (read: not in someone's hand or braced against their shoulder) the momentum of the firearm + the bullet + the powder is the same before and after firing. The momentum of the powder is NOT negligible. If it were so, muzzle brakes would not work.

But the fundamental idea is right: momentum is no measure of lethality. Consider being hit by a 1000 Kg vehicle moving .1 meter per second vs. being hit by a .1 Kg ball moving 1000 feet per second. That's the same momentum both times, but you will bounce off one and be killed by the other.
 
As respectfully as I can, after being told I'm arrogant for tactfully stating the obvious, I have to tell you that you don't even know enough about physics to know why you're mistaken. It's extremely clear--indisputable--from what you've written. You would have to take at least two semesters of calculus and two semesters of physics just to get to the point where you could understand a physicist if he told you why you were wrong. Why not listen to people who know the subject?

I do listen. That doesn't mean I'll always accept everything I'm told just because it came from someone with a degree. I may be more apt to take them on their word, but don't give the statements unequivocal credence.

That said, the particular concept you see me arguing is one that I don't view as legitimate, having no practical application as an intangible, undemonstrable force. You can show people torque generating rotary motion. Lateral force can be shown to move objects. Same with pressure or mass under gravity. You can demonstrate fluid dynamics visually and easily explain application. But the passive force in question here is much more easily explained as resisting force than applying any. Just makes a lot more sense practically, is why we call supports supports, not anti-gravitational variable force applicators. Our homes are full of load bearing walls, which will never be referred to as walls that push the roof up against the force of gravity.

As well, your taking issue with some of my terminology. Part of it is a result of not having taken physics or using the textbook terms with any frequency. The other part, as I mentioned, is to leave no confusion, a la saying things like rotational torque, a redundant statement that I already clarified my reasoning behind. I deal with torque every single day. I'm well aware that it cannot describe anything other than rotational force.

Physics is science, not something you can learn from your buddies. It's the hardest field of study there is. Math is hard, and getting a math major is a joke compared to getting a physics major. I know; I majored in physics and minored in math. I have enough credits for a math major, but I elected not to take one of the requirements so I could take a different math course of more use to physicists.

You can't pick physics up from common sense or experience. It doesn't work that way! You can't even pick up a really bad and embarrassing understanding of physics without study. Momentum and kinetic energy aren't just phrases anyone can understand. They are scientific terms with strict mathematical definitions. You have to spend a great deal of time in lectures and doing problems to understand what these terms mean.

Your confusing use of bolding makes me wonder if you know what "mechanics" means.

Why is it confusing? You're suggesting that engineers who work in a field totally unrelated to firearms and ballistics, who really don't deal with mechanical applications at all professionally based on the ones I've known, are the ones we should listen to on those subjects? I suppose I could have highlighted "EE's" (why the possessive apostrophe, BTW?), but since they were the engineers to which that statement referred, I figured it wasn't necessary.

Moreover, my point, and the reason I took a bit of a hostile tone, is an insinuation you made and continued into the next post, is one which is handed down from academia all too often, basically saying if you didn't go to college and earn a degree, you're an idiot who shouldn't speak. Maybe that's not what you meant to imply, but that's how you came across. Saying "I humbly suggest" and then following with the condescension you did is akin to plastering a "stay humble" sticker on your Pagani supercar.

As for what I do and don't know, nope, never gone to school for physics. Or engineering. But I've figured out enough on my own to design & build complex precision machines from raw materials that work, and work well, the first time out of the gate without consulting anyone and, more often than not, without fully designing the thing on paper or in CAD. I'm not going to derail the thread going back and forth with you about what I do and don't understand or can & can't do, but will be happy to discuss & demonstrate that privately.
 
My undergraduate degree is in physics. And I would classify myself as a hard-core experimentalist. The writers I like are some you may never have heard about: P O Ackley, and Harold Vaughn for example. So I do have great respect for practical results.

Are you seriously proposing that Ohm's Law, Conservation of Momentum, Boyle's Law, and Kirchoff's Laws are only general approximations that may or may not hold, and of little use? I assure you my friend, it is not so. To be granted the status of physical law, a result has to be replicated many times by many people, and shown over and over to hold.

There are some things in the world that we can model extremely well. Other things are harder. Internal ballistics as a function of pressure and bullet mass are very well understood, and the real world results match the model within our ability to measure. Wounding ballistics is hard. Nobody I know of has a model for that, at least one that I believe. AFAIK, we can grub out some rules of thumb, and that's about it. Hanging your argument on lack of that model is awfully flimsy.

Congratulation on your degrees. That's wonderful. Now step outside. Bring some bug spray, maybe a Thermacell. Some boots with thick socks, a good hat, some long pants, that's it. Now, out here, what we're
trying to extrapolate (if that's the proper mathematics term, after all, I'm just an ignoramus, by your standards) is the essence of the meaning behind the ballistics data as it pertains
to our usage practicum (help me out here, never matriculated, I'm just dumb as a stump) in harvesting game and pest animals. I'm not postulating that any of the laws of physics are
at all flawed. What I'm suggesting is that you are all arguing niggling and parsing points on math and physics theory, you're completely overlooking the "lack of a model" which
denies most of your arguments of ballistic power any substance in the perception of the practical hunter. As flimsy as it may seem, one would certainly hope there's a point to
all this mathematics theory /model construction and examination.

I will, however, heartily admit that I'm having a hard time understanding what Electromotive Force, measured in Voltage, Instantaneous Current, measured in Amperes, and
Resistance, measured in Ohms (i.e. the components of Ohm's Law) or Kirchoff''s Law, for that matter, has, in any way, to do with the field Ballistics. Oh, us pesky Rednecks!
Always trying to find tangible value in a thing.
 
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Congratulation on your degrees. That's wonderful. Now step outside. Bring some bug spray, maybe a Thermacell. Some boots with thick socks, a good hat, some long pants, that's it. Now, out here, what we're
trying to extrapolate (if that's the proper mathematics term, after all, I'm just an ignoramus, by your standards) is the essence of the meaning behind the ballistics data as it pertains
to our usage practicum (help me out here, never matriculated, I'm just dumb as a stump) in harvesting game and pest animals. I'm not postulating that any of the laws of physics are
at all flawed. What I'm suggesting is that you are all arguing niggling and parsing points on math and physics theory, you're completely overlooking the "lack of a model" which
denies most of your arguments of ballistic power any substance in the perception of the practical hunter.

I will, however, heartily admit that I'm having a hard time understanding what Electromotive Force, measured in Voltage, Instantaneous Current, measured in Amperes, and
Resistance, measured in Ohms (i.e. the components of Ohm's Law) or Kirchoff''s Law, for that matter, has, in any way, to do with the field Ballistics.

I've withheld information about my degree for a long time on this thread.

I've also spent plenty of time doing practical ballistics work in the field. I've designed and built my own strain gauge pressure measuring device, and I did extensive designed experiments on the M855 cartridge for the Lake City Army Ammunition Plant. I solved a problem that had baffled their engineers for years. Don't think for a minute that because I understand a bit about theory that I know nothing about practice.

The original question was, why do torque and energy come out in what sounds like the same units? That's a physics question. I have given a physics answer.
 
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One reason I studied physics: One day in the Eyring Science center, a young coed fainted on the floor, right in front of me. I was stunned. I did not know what to do. One of the physics profs was right there, and without hesitation took charge of the situation. He proceeded to systematically analyze and handle the situation, and I saw that he was applying the systematic thought process that his field of study had taught him. I didn't know what to do, and his training told him exactly what to do. It made quite an impression.

I don't see what A) physics has to do with first responder/first aid training or B) why you don't seem to differentiate between education and training. Similar and with plenty of overlap, but not synonymous. One is putting information into your brain, the other is drilling into you how to use the information in your brain in a practical way without having to think it through. We educate people in colleges, we train them in academies.

One correct form of many plurals is to use an apostrophe. If you are filing your taxes, you might file multiple Form 1099's. The same is true of EE.

I wasn't speaking to you, but no. Using an apostrophe to pluralize regular nouns is incorrect. It is often an accepted use following numbers (1990's, your Form 1099's), but not for Electrical Engineer's; whether spelled out or abbreviated, it creates a singular possessive with a noun. And using it after the "s" creates a multiple possessive. Plural form of regular nouns is just an "s", or sometimes "es":

https://www.grammarbook.com/punctuation/apostro.asp

And think about this for a minute: Gravity is pulling down on the dirt in your yard. What keeps it from collapsing inward, like the planet Vulcan? By Newton's Second Law, with no countervailing force upward, your yard has to collapse into the Earth. So either there is a countervailing force, or Newton's Second Law is wrong.

Wouldn't that be 1st law?

At any rate, I don't have to think about it for a minute. You, the dude with a physics degree, wants to call it opposing force. Me, the guy who actually builds all kinds of things that support mass under gravity, is going to call it structural integrity of the substrate.

Here, let's look at the way you're applying Newton's 1st law in another capacity: Pressure. You would argue that the chamber on your rifle, which is being pushed outward on to the tune of 50,000+ PSI, has an equal and opposite force pushing back in, keeping it all together. In metallurgy and pressure vessel design, however, we call it tensile yield strength. We're never going to look at it as the material exerting enough opposing force, always as having enough TYS to contain the forces within, that omnidirectional force of pressure. Furthermore, if it were as simple as the material pushing back with equal & opposite force, we wouldn't have to consider such things as length or circumference of vessel sides, using toroidal ends rather than flat or simple hemispherical, etc.

Now, if you want to discuss things hanging in mid air because of lift forces generated by heat differential, air current or other means, sure, calculating that stuff is fun.

I'm not the cretin you seem to think I am, just don't spend my days studying mathematics or building theoretical models, ergo don't see the world the same way you do.
 
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But the fundamental idea is right: momentum is no measure of lethality. Consider being hit by a 1000 Kg vehicle moving .1 meter per second vs. being hit by a .1 Kg ball moving 1000 feet per second. That's the same momentum both times, but you will bounce off one and be killed by the other.

Now if you dropped that 1000 kg vehicle on someone, at 0.1 meters per second, I will bet, the person will be just as dead as if they were hit by a 0.1 kg ball moving 1000 feet per second! And probably a little flatter!

Don't try this at home. :D
 
Having a systematic method of handling new situations is a good thing. The physics prof had that because studying physics ingrains a logical approach that applies in a great many situations. He knew exactly what questions to ask and what actions to take because his mind was educated to a structured problem solving approach. If you have that skill, you can always get the laws and formulas. The power is in the scientific approach.

Now as to whether your chair is pushing upward on your butt, I can't explain it any better than I have. Sometime in the Hereafter, you and Isaac Newton can wrestle out the issue.
 
Having a systematic method of handling new situations is a good thing.

I certainly won't argue that, but my own life experience has shown me that people who can apply systematic, structured methods they learned in one discipline in novel ways, or especially in a universal manner, are the exception, not the rule. Assuming you subscribe to Cattell & Horn's work, most people's intellect, especially adults, is much more Gc type.
 
I certainly won't argue that, but my own life experience has shown me that people who can apply systematic, structured methods they learned in one discipline in novel ways, or especially in a universal manner, are the exception, not the rule. Assuming you subscribe to Cattell & Horn's work, most people's intellect, especially adults, is much more Gc type.

Well, it may be the exception. Perhaps it is.

I have spent a career dropping in to unfamiliar industrial processes and systematically solving problems. My friends and I have worked on everything from Eggo Waffles to air bags to mortar rounds, to minting coins, to nuclear fuel processing. To me, it doesn't seem that uncommon. All my friends who studied chemistry or some form of engineering or physics seem to be able to do that as well as I do.
 
That said, the particular concept you see me arguing is one that I don't view as legitimate, having no practical application as an intangible, undemonstrable force. You can show people torque generating rotary motion. Lateral force can be shown to move objects. Same with pressure or mass under gravity. You can demonstrate fluid dynamics visually and easily explain application. But the passive force in question here is much more easily explained as resisting force than applying any. Just makes a lot more sense practically, is why we call supports supports, not anti-gravitational variable force applicators. Our homes are full of load bearing walls, which will never be referred to as walls that push the roof up against the force of gravity.
Unfortunately, if one adopts nonstandard terminology or explanations for discussing established concepts, then misunderstandings, and likely hard feelings will develop.

Intuitive or not, the idea of passive forces is a standard concept in physics. Not just that, but it is a necessary concept based on one of the three basic laws of motion. It may not make sense to some people to talk about a load-bearing wall pushing up against the roof it is supporting, but if those persons wish to communicate the concepts accurately then using nonstandard terminology or attempting to construct a contradictory explanation is not a recipe for success.

It is unfortunately true that not all accurate concepts are intuitive.
For two objects having the same momentum you want to be struck by the heavier object since it will inflict less damage.
It is certainly an oversimplification--it's oversimplified so much that it can not be correct. While it is true that if two objects have the same momentum, the slower moving (heavier) object has less POTENTIAL to do damage, it's not a given that either will do damage at all, nor is it a given that there will be enough difference in the energy to make a practical difference.
I certainly won't argue that, but my own life experience has shown me that people who can apply systematic, structured methods they learned in one discipline in novel ways, or especially in a universal manner, are the exception, not the rule.
In my experience, people are either problem solvers/troubleshooters or they aren't.

That doesn't mean that a person who is good at problem solving/troubleshooting will automatically be good at solving any kind of problems regardless of the field of study involved. But it does tend to mean that if you have a problem that needs solving, you're better off taking a problem solver and giving that person the background involved to get "smart" on the topic rather than starting with someone who has a lot of knowledge relating to the topic at hand and trying to teach that person to be a good problem solver.

****************************************

I hate this kind of discussion because it almost inevitably degrades in a predictable manner.

The people with lots of experience but little formal study automatically assume that anyone with a degree must be inexperienced in the real world and usually make the accusation explicitly as if education is proof of lack of real world experience. There are people like that, but there are also people who have both experience and education.

The people with lots of education point out the inevitable errors that occur when someone who hasn't had a lot of education starts trying to talk about a topic is difficult to discuss properly without a certain level of formal training.

Both sides take the comments as personal attacks--which, admittedly is a reasonable response at least some of the time. Then it's time for the anatomy measuring contests to begin. And that entrenches both sides even more firmly in their respective positions and generates more ire.

The bottom line is that there are highly educated people who are practically useless. And there are people with lots of real-world experience who have no understanding of basic scientific principles.

But there are also highly educated people with tons of real-world experience and practical knowledge. Just as there are people with little formal education who have learned a lot about science through dedicated informal study.

I would like to point out one issue in spite of the fact that I know it will make some people angry. Excepting the very few people who are in the same intellectual category as Isaac Newton and have the ability to develop and formalize general scientific principles on their own, without help, it is unlikely that a person will be able to gain a reasonably accurate understanding of science without some significant level of study whether that study is formal or informal. Even Newton studied formally and built upon the foundation that study provided. Anyway, a person with real-world experience may be able to apply it constructively, but if they resist/avoid any sort of scientific study, it does mean that their understanding of the underlying science will be limited or flawed and it means that their ability to explain those foundational principles to others will also be limited.

The same sort of thing applies to a highly educated person who doesn't want hands-on type of work that would provide them with real-world experience. I've run across some highly educated folks who seem to revel in doing all their work inside their head and then tasking underlings to do the actual implementation. They are going to be lost when they have to do something approaching practical no matter how well they understand the science.

I don't have a good solution for the inevitable impasse because any decent solution involves accurate self-assessment and, unfortunately (regardless of education or experience level) the people most in need of accurate self-assessment are actually the ones most unlikely to be able to accurately self-assess.

That said, it is certainly possible for people in either camp to engage in scientific study or to "get their hands dirty" and acquire real world experience if they are so inclined.
 
Wow...I had no idea I would have stirred up such a hornet's nest with this one. It would seem that my major misunderstanding of the subject was one of terminology. I had no idea that the world of physics and the world of engineering use similar, albeit separate terms to describe related phenomena. My education is in marketing, but the majority of my career experience has been repairing swimming pool equipment. Which by definition makes me a jack of all trades, master of none. I have to have some knowledge of physics in the sense I deal with fluid dynamics and hydrostatics...electrical concepts of resistance and induction (motors and relays), chemistry, and a little geology and hydrogeology. (First time you ever see an empty 60,000 gal swimming pool float up out of the Florida soil, you start to take an interest in hydrogeology)
This is all to say I have had very little formal instruction physics or engineering. I have a very specific practical experience of these concepts, and the common vernacular I use to describe these phenomena apparently do not translate well to academia. Now, that's ok, I'm always down to learn new things and welcome the opportunity.
I now know, if I'm ever at a dinner party with a group of physicists and engineers, the topics to avoid would be Politics, Religion and Ballistics:D
 
I suppose I could have highlighted "EE's" (why the possessive apostrophe, BTW?)

I should let that pass, but...look up grammatical rules for plural acronyms.

EE's don't specialize in mechanics, which is what we have been discussing, but they have to study the subject as undergrads, and they are very smart people.

Moreover, my point, and the reason I took a bit of a hostile tone, is an insinuation you made and continued into the next post, is one which is handed down from academia all too often, basically saying if you didn't go to college and earn a degree, you're an idiot who shouldn't speak.

That's all you. You choose to take it that way. I'm not responsible for your decision to be offended.

Lots of brilliant, highly educated people know nothing about physics. What I said was that people who knew nothing about it shouldn't pretend to teach others. That's 100% true. I am competent to talk about law and certain topics in math and physics, and I also make the best pizza in the universe, but you won't see me wading into an oncologists' forum and trying to tell them about curing cancer. My lack of knowledge might not make me an idiot, but my decision to pontificate anyway would make me look like one.

Things untrained people write about physics are generally worthless. That's not condescension. That's a fact. Universities and degrees exist for a reason.

As for what I do and don't know, nope, never gone to school for physics. Or engineering.

I know.
 
All engineering and physics students take a very solid physics class. In my case, it was two semesters my sophomore year. I started out as an EE, and changed my major to physics after two years, with practically no loss of progress. As far as I know, any competent EE, ME, ChE, or CivE major, junior year or later, is well grounded in not so basic physics.

It's also helpful to understand that STEM engineering students have a little different learning culture than other majors. It is (or at least was, back in the day) considered entirely proper to bluntly challenge the professor. It's part of the learning process. One day in a humanities class, I forgot where I was and did that to the professor. In that setting, and the way I did it, it was out of line. I embarrassed her. In a different setting, it would have been fine.

Part of the culture was challenging each other, often very frankly. There would be great raging debates after class. There was nothing mean about it, it was just the way we learned. After it was over, people had a much clearer understanding of whatever principle was being discussed, and everybody benefited. The discussions might be spirited, but never mean. People who didn't go through that kind of experience sometimes don't quite understand that it was all just great fun and learning, and nobody got angry. When you start talking physics, you pretty much invite that kind of interaction, because that's how we learned our topic.
 
Part of the culture was challenging each other, often very frankly. There would be great raging debates after class. There was nothing mean about it, it was just the way we learned. After it was over, people had a much clearer understanding of whatever principle was being discussed, and everybody benefited. The discussions might be spirited, but never mean. People who didn't go through that kind of experience sometimes don't quite understand that it was all just great fun and learning, and nobody got angry. When you start talking physics, you pretty much invite that kind of interaction, because that's how we learned our topic.

Going back and forth with you doesn't bother me, in fact made me re-evaluate the way I look at and apply the concept of passive force, although I still feel it more useful in my world to consider it resistance to force rather than application of opposing force. Regardless, I know more about the subject today than yesterday, thanks to you and John. As well, John pretty much said as much as Steve, but in a way that isn't highly offensive with the stench of conceit. If I tried to impart my professional knowledge on friends the way Steve has done here, I wouldn't have any. One can be the very best in their field, but with the wrong approach to sharing their knowledge, nobody will be listening. Telling people to shut their mouths and let the professionals run the discussion does exactly what John said:

Both sides take the comments as personal attacks--which, admittedly is a reasonable response at least some of the time. Then it's time for the anatomy measuring contests to begin. And that entrenches both sides even more firmly in their respective positions and generates more ire.

I'm still listening to you, John, Dave. Steve? Not so much.
 
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