Hi all, Lets see how well this idea flies: We experiment with objects undergoing changes of velocity. We model this information with the equation f=ma. The empirical evidence consists only of measurements of distance and time. We do not know what force is or what resistance to force is. We deduce from the patterns in the evidence that both of these must exist. But, we cannot learn their natures from the evidence. We have only distance and time to work with. These are two unique properties that we experience directly. We move across distances during periods of time. What we observe from the experiment is acceleration, and, it consists of distance and time. There are four properties involved. Two are known unique properties. The other two, force and resistance to force, are not known unique properties. They may be related to each other. They may even be related to distance and time. There may be a single fundamental cause that manifests itself differently under different circumstances. In other words: Perhaps unity exists at the fundamental level. At this beginning point we cannot tell whether or not that is the case. We decide to theorize about the meaning of f=ma. There are different possibilities of choice. If we assume that the natures of force and resistance to force are fundamentally different properties, then we must theorize into existence a unique nature for one of them. We give them names. One is named force. The other is named mass. Historically, mass was chosen as the property to receive its own unique interpretation. It is arbitrarily assigned a fundamental uniqueness. By this act, it joins distance and time as indefinable properties. Force can then be defined in terms of mass, distance, and time. So far, the act has consisted of words and ideas. The equation is not directly affected. Now though there has been created a need to invent a new unique unit of measurement for mass. Its units cannot be defined in terms of other pre-existing units anymore than can those of distance and time. Mass is assigned units of kilograms. There are now three indefinable units of measurement; kilograms, meters, and seconds. By this act, the invented uniqueness of mass as a fundamental property becomes solidified into the equation. The equation which began as an empirical expression has become part of a theory. The equation becomes subservient to the theory. This theory will now infect itself into all higher level theory that includes this definition of mass. What difference does this make? If unity does exist at the fundamental level, we have not only missed the opportunity to discover this, but, we have introduced theoretical disunity into our analysis at its very beginning. James
Hi James--- I've moved this thread to pseudiscience because I don't see anything particularly scientific about this discussion... F=ma is a definition of "force" (which one cannot measure) in terms of things that CAN be measured, namely mass and acceleration. Newton made it very clear that his laws were empirical, in the sense that he didn't understand WHAT force actually was. He didn't really like this fact. In terms of wat force actually IS, we have a very good (I would say nearly complete) understanding of the mechanism by which one particle can influence another.
Hi Oli, QUOTE=Oli;2210596]Actually, I think it's an intriguing approach. If I understand what James is getting at.[/QUOTE] Thank you Oli. It is in fact, I think, the most important question that could be asked at this point of development of theoretical physics. However, There would be much more to discuss and it would require contradicting current theoretical interpretations. It is best to let it lie. You will notice that my opening message was there long enough to determine that there was not going to be discussion right from the start. No hard feelings here. James
James Putnam: We start not with the equation F=ma, but with a theory (or an idea that has the potential to become a theory). We start with a vague concept of "force" as a push or a pull, an influence exerted by one object on another, often by physical contact between the two. Along with that we have well-defined concepts of distance and time, from which we derive the concept of acceleration. Experimentally, we can quantify precisely the size of a force (push or pull), and thereby eliminate the initial vagueness of the idea. Then, by further careful observations, we deduce that force and acceleration have a linear relationship. The constant of proportionality in that relationship we choose to call "mass". Subsequently, we find that this constant usefully characterises objects in many ways. It is a choice to define the metre, the second and the kilogram as the "basic" units, in which case the unit of force becomes a derived unit. This is not necessary. We might have chosen instead to define force, length and time as the basic units, in which case mass would be a derived unit. Or, we could have chosen mass, length and force as basic units, and derive time. The particular choice that has been made, however, is not completely arbitrary. It is the one that is the simplest for us to visualise, given our intuitive understandings of objects, motion and time.
Hi James R, I am not going to pursue it. I believe what I said was accurate. It certainly is not pseudoscience. Like I said, thanks anyway. No hard feelings. James
Well for starters there are lots of points here that are incorrect. For starters force does have units. They are called Newtons. Ten Newtons equals one kilogram. And yes force is easily measureable. second Mass is measurable. Take the weight of an object. Than divide it by the force of gravity, 9.81 meters per second, that is mass. Mass is defined as the amount of matter in an object. Also, Force causes acceleration, acceleration causes motion. And motion is measured as distance most commonly as meters. This is shown in Acceleration=net force/mass or Newton's second law.
And also the equation you gave f=ma is the same thing as what i said above except it is solving for force not acceleration. And also, It isn't just "F", it is sigma F, that means net force, and that means the end force which would factor in forces that resist the initial force like friction.
Sorry James, I didn't mean for it to sound like you did. Bentheman moved this thread to the pseudoscience forum. That was his opinion, not yours, about where it belongs. I was referring only to the fact that that is where it currently resides. I just do not wish to fight for every point against that stigma. I prefer to let it lie. I think this is a good forum. I have no complaints. James
fedr808: I think James Putnam knows all that already. But if you're in the business of correcting people, it's a good idea to get it right yourself... Newtons and kilograms cannot be equated, since they have different physical dimensions. 1 Newton is 1 kilogram.metre per second squared. 10 Newton is 10 kg.m/s^2, which is a different beast to 1 kg. That's 9.81 metres per second squared, and it's not the "force of gravity" - it's the acceleration due to gravity.
I know that, and just to prove it i can also say that it's negative 9.81 meters per second squared because it is acceleration. But we dont say 9.81 kilograms per meter squared, we just say 9.81 kilograms.. I didnt want people reading my post and squaring the results of the equation and getting mislead.
And also, it's actually 10 newtons to 9.81 kilograms of weight. Because 1 kilogram of mass is equal to ten newtons, and 1 kilo of mass equals 9.81 kg of weight.
Yes, but tell us about the missed opportunity. What are we missing and how do we find it? And as for being in Pseudoscience, you should be thankful. In Pseudoscience you can talk back to the professionals in ways that are not permitted in the hard science forums. You can say your piece, defend yourself in the same fashion that you are addressed, and dish it out as well as take it. If you don't do that you will fail to convey your ideas which is what you want to do isn't it?
well I first learned about electronic circuits so I tend to equate the concepts of mass and inductance force and voltage acceleration (time derivative of velocity) and the time derivative of current Please Register or Log in to view the hidden image! http://en.wikipedia.org/wiki/Kirchhoff's_circuit_laws
