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Thread, University Physics Sixth Edition Written by Francis W. Sears, Mark W. Zemansky and Hugh D. Young Published By Addison-Wesley Publishing Company Copy on my shelf-Reprinted with Corrections May 1983 The section on motion in a plane did not in any way teach me that there was such a force as centrifugal force. I was wrong to suggest that I had been taught differently than what is being described as established Physics in this thread. Any misconceptions are my own, and not assignable as faults in “our” understanding of motion. From the section on motion in a plane (copied without permission.) “Some readers may wish to add to the forces shown in Fig.5-12 an outward, “centrifugal” force, to “keep the body out there,” or to “keep it in equilibrium.” (“Centrifugal” means “fleeing a center.”) Let us examine this point of view. First, the body doesn’t stay there! A moment later it will be at a different position on its circular path…” “Those who wish to add a force to “keep the body in equilibrium” forget that the term equilibrium refers to a state of rest,or of motion in a straight line with constant speed. Here, the body is not moving in straight line, but in a circle. It is not in equilibrium, but has an acceleration toward the center of the circle and must be acted on by a resultant or unbalanced force to produce this acceleration. In this example there is no outward force on the body!” Regards, TAR

SwansonT, I thought the solenoid setup asked my question. How does the energy get from one end of the shaft, to the other, in relation to the momentum getting from one end to the other? Regards, TAR

Thread, OK, maybe a little clearer. Speed is just a scalar, Velocity is vector, with a direction. I think I got misdirected by a KE formula I saw somewhere, that had a v in it. And still a bit cloudy on the impulse thing, as it seems an impulse can have a definite direction in which it is acting, and a mass does not seem to have to move, to carry the impulse. I am currently, mentally considering a solenoid with a 100 meter, inelastic shaft attached inline to the end in which direction actuation would take the solenoid, and with a hundred meter, inelastic wire, attached to its back end. During activation of the solenoid, a force, or impulse will travel along the shaft and act upon an item placed at the distant butt end of the 100 meter shaft. Similarly a force during activation will pull on the wire and be transferred to the other end of the wire (which is attached to a small loose mass which with move in the direction of activation) What is the speed of the impulse traveling along the shaft? Speed of sound? Speed of light(magnetic force, strong force, weak force)? Speed of the soleniod? How about the speed of the impulse along the wire? How does the momentum get from the solenoid end of the shaft to the far end of the shaft, in that particular direction, if no mass moves more than the throw of the solenoid? Is there not a directional component of the impulse that belongs with the analysis? How does one satisfy themself with a center of mass formula, when the important parts of what is happening are happening 100meters away from each other? Regards, TAR

StringJunky, I think you are right, that people envision themselves as much more capable than they are. The example I use, to humble myself is when I think I would do something differently "if I was president", is the thought that if I actually had the capability to BE president, I would at least be chairman of the local school board, or head coach of the little league team. (which I am not) But, in regards to the threads that have exceeded their shelf life, I would like to submit the other side of the expert coin for consideration. There is the 'joy of learning'. It is a fantastic feeling to stand on the North Rim of the Grand Canyon and hear the story about when the spanish explorer first came upon it with his party, he sent several of his group down to the river for some water for dinner...they came back 3 days later. He had know idea of the scale of the thing he was looking at. There is a pleasure in gaining an insight. There is a pleasure in sharing an insight. There is not much pleasure in being told one's insight is old news, or is wrong. So what, the Grand Canyon is just a big rent in the surface of the Earth. Millions have seen it, measured it, documented and studied it. It is established fact...but still fantastic to experience for the first time. Regards, TAR

Studiot, No, not a problem per se. But KE and Momentum are not mutually exclusive items. They are used to figure different things about a moving item. My concern is that the momentum of a moving object carries a directional component and when the momentum is transferred to another item during a collision it causes the other item to accelerate in the direction the first item was moving, as the first item decelerates or perhaps accelerates in the opposite direction. The kinetic energy is also traveling with the first mass, and transfers to item number two. Just an amount though, without a direction. Why does the direction of an impulse not matter? How is that desk prop with the steel balls touching each other analized in terms of momentum vs KE when the left ball is dropped on its neighbor and the far right ball takes on the momentum. The middle balls never move, they never change their momentum, but some KE travels through, in a certain direction. Regards, TAR

Never connected it before, but perhaps the empty parenthesis could be ivory, as might be used for white piano keytops.

PeterJ, I am looking at a one page picture of the Divine Theme Chart IX by Meher Baba May 17, 1943, given to me by a woman (co-worker) from India, who I used to talk to about her beliefs. I see the stone forms, metal forms, vegetable forms worm forms fish forms bird forms, and animal forms, that are part of the winding process, and the subtle world and mental world that are part of the unwinding process or the realization process that brings one to the god state as conscious of the gross world and the master's soul, both. Being familiar with the theory does not make it literally true. All the components are actualities, but what of it is physical and what of it is metaphysical is rather obvious. What of it is logical and real and meaningful is apparent. I can understand my version of the master's soul, without learning a darn thing from Meher Baba. I can tell the difference between what is logical and sensible, and what is illogical and nonsensical without knowing whether my sanskaras is decreasing or increasing. I also have read the Koran twice. That does not mean I am not in favor of being good, in the eyes of Allah (figuratively) or that I think Mohammed was visited by Gabriel in the darkness of a cave, and told the real meaning of the Old Testament. There are some things that are literally true, and reincarnation is not one of those things. It makes no sense, and does not work. Something you agreed with, earlier in the thread. I might not have the knowledge of the theory that you have, nor do I have the knowledge of the Koran, that a scholar who read it in the original Arabic might have. I still can know that Mohammed could not have been spoken to, literally, by an angel...because there is no such literal thing. Angels are made up, figurative things, that stand for actual human consciousness. Regards, TAR I also have Kant's Critique of Pure Reason downstairs, and there is a bookmark in it about 1/3 the way through. I have not read a page in a long time, but I used to read it about a page or two at a time...and think about and integrate what I read, into my own understanding of the world and consciousness and metaphysics. I don't know nothing about this subject. Accusations of ignorance on my part are not true; you will have to come up with another argument. Alan, I joined this thread in support of your thesis. Now I am getting neg reps from you and PeterJ because of my snarky sarcastic comments pointing out the illogic of your mystical beliefs. Deserved perhaps because the remarks were hurtful, but within the context of this thread, it would be more intellectually honest if you would cast the same suspicions of nonsensicality upon your own beliefs...if a belief of yours is as equally grounded as a belief of Meher Baba. Regards, TAR

PeterJ, So, regardless of my defense of Western thought, in reference to this thread, if Westerners commonly do not believe in reincarnation, are they being logical, or illogical? Does Karma and Reincarnation make sense, or is it nonsense. Are they a real fact of life, or are they religious beliefs. Is god a figurative thing, or a literal thing. Are the rules of reincarnation made up, or carefully researched and documented. Can anyone tell the past lives of an individual by some objective means? Or must one be a believer to believe it? Regards, TAR PeterJ, You base your conclusion, that Western Philosophy is a failure, on a strawman argument. You find a question that has no answer, according to logic, and suggest Western Philosophy is a failure, because it can't answer the question. I would say the contrary, that Western Philosophy has carefully and logically defined the difference between science and mysticism. Regards, TAR

Phi, StringJunky and Imatfaal, Properly rebuked and advised. I will attempt to refrain from throwing guesswork at questions where rigor is required...or where rigor has already been applied. But, for the record, I still enjoy figuring stuff out for myself and have a hard time accepting other people's conclusions, without fully vetting their premises. Regards, TAR I guess I still have to learn that others have already been there and done that, and it is OK to trust their judgment. I suppose that is where peer review comes in. If its established science, the premises have already been vetted.

PeterJ, Progress toward what? If you are aware of the end game, why are you not there already? What are you doing hanging around here in your mortal shell? Regards, TAR Or did you just come back to pick up stragglers? Sorry PeterJ, you said you did not wish to argue, so I will withdraw, if I am not helping here. I seem to be rather already decided on some of these issues, and therefore not much fun to talk to, about them.

Phi, OK, I thought I was contributing, and have some good angles from time to time. I guess not so much as I thought. I will scale it way back, and be skeptical in private. Regards, TAR

SwansonT, OK, I forgot there was an issue determining both a particle's postion and its momentum. I will have to rethink why I think KE should be more than a scalar. studiot, I was thinking pressure washer, or cleaning my patio off with the hose set to "jet". I can direct the dirt and the built up water toward the low corner of the patio by positioning the stream in such a way as it pushes the dirt and water in the same direction as it is coming out the nozzle. Regards, TAR OK, maybe the pendulum shows me.

Mike, I vote with pzkpfw for the flawed experiment. When you throw the lizard it looks sort of like a lacross toss. You are doing something with the tube that looks more like a lever situation than one in which an item (lizard) is in circular motion. Besides, the lizard can never be in a situation where it is being directed by centripedal force, toward the center, because there is nothing outside the lizard in the radial direction, to constrain it, into a circular path. All you have is a little friction from the inside of the tube. Better experiment would be if you held the tube at your waist, lifted the far end about rib high, and spun yourself around like ballet dancer or iceskater doing a spin. Gravity would help hold the lizard in the midposition of the tube, and we could see if the tangential momentum translated in any way to a trek up the tube. Besides, it would be fun to see you get dizzy and fall down, regardless of whether or not the lizard creeped up the tube, against gravity. Regards, TAR

But as an "impulse" that comes from one direction, and is heading in one direction, can be conceptually considered as a thing, or a packet of energy, or a wave, or a particle, if this packet of energy is embodied in the mass, by virtue of its motion, does not the motion of the mass indicate a direction that the energy is taking? In discussions of energy, or potential energy and kinetic energy, a mass' position, in respect to gravity, for instance, matters. If a bowling ball is about to roll off a shelf, it is going to eventually apply a force on the floor, not the ceiling. The kinetic energy of the falling ball, is going in the same direction as its momentum. SwansonT, Kinetic energy might not stick as closely to a mass as its momentum does, but the energy has to be accounted for, during an impact, even though it may not do work, and even though it may change its form...into waste heat for instance. But while a body is in motion, its momentum represents a force that will act on a stationary inelastic mass it might run into. There is a good chance that the force that got the mass moving, had a directional component which the moving body is still carrying, and which will be transferred to the inelastic body which is contacted. In this, the mass is a carrier of a force, with the directional characteristics of the force that got it moving in the first place. How does one decide which parts of this impulse is KE and which parts is momentum? Regards, TAR

PeterJ, "As for the idea that we should stick to ideas that work, this is the approach I'm recommending in the face of your determination to endorse ideas that never have worked." The ideas promoted by the Greeks and the Western Philosophers, through the enlightenment and the industrial revolution... the technological advances spurred on by adherence to the scientific method, are all ideas that have worked. Worked to bring Western Civilization to where it is. You cannot say both that Western Civilization is a good, workable idea, AND that the ideas it is based on are a complete failure. Alan, Why must one consider reality an illusion, when it is so obviously real? Why else would we be calling it reality? You require another plane of exisistence for the soul to occupy. Heaven is not a far cry from the progressing soul of the believers in reincarnation. This is your thread, figuring that Karma and reincarnation are illogical. Yet you hold to the mystical, illogical tenants of your own religion. PeterJ decries the illogic of the believers in reincarnation, because it does not work, but accepts instead that his soul is operating under specific logical rules of rebirth, dictated by the universe. Exactly how many angels can fit on the head of a pin? According to Alan. According to PeterJ. Regards, TAR Why is TAR's mysticism and feeling of belonging to the universe incorrect and Alan's way and PeterJ's way is correct, because someone wrote their imaginings, down, Alan and PeterJ read them, and decided that is the way it must be?

Thread, Well, another way to look at it, is like the "good cop, bad cop" interogation method. Many of the threads that Mike and I get involved in, are highly read, and are interesting, and people learn stuff from, and get new ideas from. I can't speak for Mike, but I know from me, I am not being willfully evil, and I am not stupid. I am stubborn though, and I overthink stuff, and I look for the "whys" when only the hows are presented. If there is an angle on a thing that does not seem correct to me, I push on, looking for a satifactory take on the situation. I appreciate SwansonT's patience and time, responsponding to my posts in Mike's centrifugal thread, and I continue to post, because I don't agree with him, that my muses and questions have nothing to do with Mike's original post. I try and admit when I am wrong, and I try to explain where I went wrong, when I recognize it, and I figure that helps both the students and the teachers on the board. Sorry I have to be told a million times that I am wrong, before I see it, but I usually am holding on to some angle, that has not yet been totally explored, hence the goal post changing and the long threads. For instance, it still "appears" to a rider like there is an outward pull, and I am interested in arriving at a satisfactory (to me) answer to that question. I continue pursuing that goal, with perhaps the incorrect assumption, that someone else might also be unsatisfied. Regards, TAR

A body with relative motion (transitional not vibrational motion) to the Earth's frame of reference, got going in a certian direction by having a force applied to it, different than the forces being applied to its surroundings. This force had a vector quality associated with it. A magnitude, and a direction. Momentum is thusly outfitted. But kinetic energy is stripped of its direction and is a scalar quantity only. Just an amount, with no direction. There might be definitional reasons for this, but my speculation here is that the two, kinetic energy and momentum are related, and are not unrelated concepts. That is, when energy is added to an object or mass, by a force, it is added in a particular direction, like the cue hitting the cue ball and sending it off in a particular direction, the cue ball transfers that energy to the object it hits, with a vector included. The energy is stored in the moving mass and transferred to the item it contacts, and there is a similarity to the direction in which the force is applied to the object hit, that can be traced back along the route of the moving object to the point at which a force in that direction, first acted upon it. So why are kinetic energy and momentum two diffent concepts, when they are so closely related, conceptually?

PeterJ, Well wait. We can't leave this, you have described the last 2000 years of Western Civilization as a failure. What are your parameters that would describe success? We have, at least in my country, quality of life, riches, technology, medicine, neighborhood, and friendship and coordination that absolutely works to cause millions of people to exist and procreate and enjoy life, liberty and the pursuit of happiness in peace and security, with respect for each other and respect for the law. This nation of mine was built on the back of Judeo/Christian values and the philosophies of the Greeks. You think caste systems in India are somehow more of a success than this? Regards, TAR

SwansonT, I shook your martini again, but only to keep you drunk and easier to argue with. My "understanding" of motion includes the inertia or the kinetic energy within a body. I understand, that in the discussions of what forces are "added" to the body in circular motion, there are only the forces accelerating it, changing its direction toward the center. However, the body does not wind up in the center, there is a tranverse, tangential effect that the kinetic energy of the body has that is countering the forces pulling toward the center. Mike and I and RobbityBob1 are not saying that physics is wrong, we are just pointing out this kinetic energy effect, like you pointed out a thing present that your collegue was not considering. I do not mind musing about the new paradigms Mike talks about. Neither he nor I have any power to, or desire to change the laws of physics. What is true, will remain true, no matter what we think, or no matter what the equations say. There is always room to point out, a real effect that someone else has failed to build into the equation. Regards, TAR

PeterJ, Do you draw a distinction between mysticism and metaphysics? I have not read your blog, but I think I have heard your "only one way metaphysics works" and your demonstration of it did not convince me, nor did I see its logic. I thought you were wrong, and your logic did not force your conclusion. I did not like, nor did I agree with your one way metaphysics works. Years ago I had an insight about the way we internalize the world in the folds of our brains. Like the reflection on a lake, all folded up. The world actually exists, and the reflection actually exists, and the surface of the lake actually exists. One does not discount the others, they all are exactly what they are. But this idea extends to the idea of a model, and the idea of the thing being modeled and the idea of the thing doing the modeling. Any discussion of the human mind, and human thought, that does not include these three components, to where I can parse the discussion into these components, is missing something in my estimation. When I talk of magic, I am speaking of considering something that is happening in the folds of the brain, that does not have an analog in the real world. You can imagine yourself sitting on the moon in a bathing suit, eating bon bons, but its not likely to actually happen this afternoon, to where I can see it happening. If the senses, our senses bring an analog version of the world into the folds of our brains, that is one thing...but the folds in our brains do not affect the world back, without a mechanism to do so. We can build the patterns that exist in our minds back onto the world, but we only have a certain reach. Beyond that reach is the realm of mysticism. But metaphysics deal exactly with those things within that reach we have of transferring the patterns in our brains onto the world. I don't wish to close out any thought about the way things work. I just like making a distinction between those ideas that work, and those ideas that do not work. Regards, TAR In other words, don't tell me figurative stuff and tell me it is literally true. Show me the literal mechanism by which Sally's reflection of the world leaves Sally's brain and enters Billy's baby brain. Show me that research, that follows the mechanisms and the cause and effect through. In other than a figurative manner.

SwansonT, I may have misread your account of your refreshing conversation with someone working on a problem where you pointed out an angle he was not taking into consideration, when the results did not match with what the "effect" predicted, but it sounded a little like you thought a little out of the box, he/she was confined to. You did not suggest physics was wrong, you just pointed out another way to look at, that would explain what was going on. You were not adding a complication, you were noticing a contributing factor to the results. RobbityBob1, By the pictures of the centrfugal pump you showed, it looked like the propellers/impellers were directing the fluid in a direction tangent to the outside circumference of the pump, and the only outlet for the pressure going out in all the tangential directions was one particular tangential path. It was not a radial outlet. The only thing that made it centrifugal, or center fleeing is that the inlet was near the center and the fluid was pushed outward by the fins, winding up leaving the circle by a tangential path. Regards, TAR Studiot, You make an interesting point. I took my highschool physics in the late 70s. They might have taught me something that is no longer taught, because it conflicts with some results or another. Interesting to me, because engineers and physicists had no problem building things and using things that went around in circles, when I was young. Their ideas were probably not ignorant speculations, at the time. Regards, TAR So what are the odds that motion was completely understood 400 years ago, misunderstood 50 years ago, and understood perfectly again just recently? I know I am being silly, but just making the point, that you cannot tell me SwansonT understands Newton's laws, and my Physics teacher at NJIT in the 80s had no clue. Well I suppose you can tell me I didn't understand what my teacher was saying...but that's a different point. One of the videos linked in this thread, started by stating we don't know what inertia is, just that bodies have a tendency, or a desire, to keep going in a straight line. I think its OK to speculate on what inertia is. None here would say a force is required to keep a body going in a straight line. But there is a definite argument that a force was required to disturb the resting mass, and get it going in the first place. Being that inertia is the same over time, if you exert a force on a resting object, to accelerate it to a constant speed, in a sense, that force has been embodied by the mass. I would imagine there would be quite an effect resulting from the Earth slamming into a stationary wall. The force the Earth would apply to the wall would come from its inertia, in a sense. Regards, TAR

PeterJ, So what do you figure, that reincarnation does not work, but rebirth does? There are many teachings that people go by that are real to me, in their figurative context but not real in their literal claims. You figure the Eastern religions have it right and metaphysics in the West has not progressed since the Greeks. This discounts Kant's work in the area, which is rather closeminded on your part. But even if Western takes are wrong, and Eastern takes are right, you additionally favor rebirth over reincarnation, which indicates to me that there are some Eastern ideas that are shortsighted and suspect, in relationship to the particular teachings you have vetted as reasonable. Why would you doubt the research and findings of anybody in the area of mystic stuff? Metaphysics is not mystacism. Mistic things are magic things that only live in people's minds. They are arrangements of the world made by a mind onto the world. This direction is not the proper one, in my estimation. That is why I find it somewhat fruitless, to read religious texts, that base truth on what has come from someone's mind in a meditative, or drugged or otherwise altered state. Anything true, would be accessible to me, without reading the book, where I to make my own investigation. There is a difference between making the world fit your model, and having your model fit the world. If I am to believe one sage, I must believe them all. And the only way do to this is to carefully separate what is the real world internize in a human mind, and what is the human mind projected onto the world. Regards, TAR

Thread, The basis of my quiting was so I could breath (security of body, acceptance of facts.) It occurred to me, that finding a way to live without nicotine, was one of the keys (problem solving,) and Phi For All provided another key by suggesting to make smoking not an option and to board up the nicotine window (achievement.) Spyman, encouraged us with all the areas in Maslov’s hierarchy of needs Esteem section. With the underlying knowledge that nicotine receptors in the brain, release dopamine, a reward chemical, and this makes a person feel good in a general non-specific way, I speculate that through our evolutionary trek we felt good, when we did things right and fulfilled our needs, and this contributed to/or developed/caused/resulted in, the reward chemicals like dopamine, and helps to establish feelings and ideas of good and right and proper. To the idea of the hundred things that make you feel good, and release dopamine in your brain, for real personal and societial reasons, I add the acts and ideas that fill each of the needs, in Maslov’s hierarchy of needs. Physiological; breathing, food, water, sex, sleep, homeostasis, excretion. Safety; security of :body, employment, resources, morality, the family, health, property. Love/belonging; friendship, family, sexual intimacy. Esteem; self-esteem, confidence, achievement, respect of others, respect by others. Self-actualization; morality, creativity, spontaneity, problem solving, lack of prejudice, acceptance of facts. We already talked about the senses, and the warm beach, and victory and achievement and making others feel good, and such, but Maslov’s hierarchy of needs, gives a nice framework in which to look to things that will release dopamine into your brain, so that smoking a stinky harmful expensive cigarette, to get the same hit of dopamine, would seem rather dumb. Regards, TAR

SwansonT, How do you get an instantaneous force if the definition of a Newton is the force required to move a kg one meter per second per second? Don't you need some time for the mass to move at a certain rate? Or in our circular example, you need the thing to change direction. How can you change direction instantaneously? In our merry-go-round example and our motor bike example we have humans experiencing an outward pull. This, I think perhaps is experienced over time, and is not an instantaneous judgment. I read somewhere that a human moment is about a second and a half, long. It makes a certain amount of sense to give humans at least a few tenths of a second to make a determination that requires signals to come from their inner ear, and nerves in their arms and signals from their eyes, and motor pulses to be sent to the various muscles attempting to keep the human from falling and hurting themselves. Seems a person would lean to keep from falling off or falling over. The direction he/she would lean would be away from the direction they thought they were going to fall. If they were feeling the instantaneous force, they would lean out, to gain their balance. They don't lean out. The situation, over time, is that your inertia is taking you out, away from the center. Like you said, the tangential motion is increasing your distance from the center. You are not so concerned with forces, as much as you are concerned with where you are going to go, if you grip fails. By the time you realize you are being pulled East, you are already being pulled North, or for a more reasonable example, if you broke the circle into the 15 degree segments we were talking about on the space station, and you were to ask the person to call out which of the 24 directions she was facing and which of the directions she felt she was being pulled in, I would bet she would lag the proper call by at least a few sections, since it takes time to sense and vocalize. Such slop should be considered when trying to figure why we feel we are being pulled in a certain direction. Regards, TAR

PeterJ, I guess I am a bit wierd. There are whole areas of human beliefs and human endeavor, that I have already made judgment on. Maybe a little reading and a little discussion comes first, but there are things that people say and do that I can only parse through my own experiences of what are possible things, and what are fantasies. It seem wierd to me however that you use mysticism and research in the same sentence. They seem to me like contradictory terms. I look for the explanations that make sense to me. I would not get anything out of a book that I have already determined is baseless on general principle. On the general principle that if you have a belief that something is true, that has no mechanism, and cannot be witnessed by others and peer reviewed, then it is a private thought you are having and has no reality associated with it, that others can embrace with a straight face and a sober mind. In other words, I have already determined that reincarnation is not possible, not workable, and not sensible. Reading another book that talks about birthmarks at the site of a deadly wound of someone that lived in town and died, being proof of reincarnation is just not the kind of research that I think is required to investigate the claims. I have a much better test. If such claims happen all the time in some far Eastern country where reincarnation is part of the religion, and the same claims are really really rare in a society who does not have those religious beliefs, then reincarnation is likely a religious belief, and not an actual fact of life. Regards, TAR for instance Moslems have the belief that if you do good you will be rewarded with rivers of honey, among other things, but researchers listening to the stories of people whose hands were sticky and tasted sweet after loved ones died, would not prove either that rivers of honey are real rewards, or that their loved one was good (i made that up, no one that I know of ever claimed such a thing)