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J.C.MacSwell

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Everything posted by J.C.MacSwell

  1. I like that.The habitat could revolve without rotating and allow the inhabitants to observe there surroundings in a normal manner.
  2. If they are at the same velocity there is no difference in translational momentum between objects of equal mass. Neither the ring nor the disc can magically gain any momentum to impart to the track, without taking it from the track, unless an outside force is involved.
  3. I think we can afford to recognize that it is possible. From there we can look at the costs and benefits of making things "homey". How thick would the lead have to be to shield as well as the highest inhabited elevations on Earth? Can any other material do it more efficiently? The cost of getting it up there is probably the biggest factor. How small a wheel could be used comfortably?
  4. You are claiming you have a design whereas an isolated physical system can change it's momentum. Are you not?
  5. Yes. The mechanical design and dam are how you go about making it more efficient. No point in building a 1000 foot high dam if you have no potential to fill it.
  6. Shield the radiation and provide artificial gravity. It might not be ideal, but surely it is possible.
  7. Yes. There is no reaction force shown when the ring is accelerated and decelerated. The traction force is a lesser component. You are adding the four stages up, as if they represent a full circuit Other than leaving some out, they are almost correct, except the end ones represent the full curve where the centripetal force direction will vary. You can claim it represents the average direction only in the case of a static track, so this is incorrect for an isolated system where the track will be displaced, and you may also misrepresent the average magnitude. Very easy to make mistakes (wrong assumptions) as the speed will vary around the curve. Something is lost to me in the translation. Do you believe the forces are proportional to the length of the arrows shown? If there are no external forces on an isolated system, the net forces will be zero. If the center of gravity of an isolated system is at rest, it will remain at rest. It cannot move, not even wobble. The system cannot gain, even temporarily, any net momentum it didn't already have. None of your explanations seemed to recognize this, and you added and subtracted momentums that you believed you gain and lost. Making more errors to one side than the other, and you magically end up breaking physical laws.
  8. Show an isolated system with no external forces. Show all the forces at one, and only one, point in time. Use arrows to show the direction of each force. Let the length of the arrow represent the magnitude of the force. If you haven't misrepresented any forces: You will see that the net force on the system is exactly zero. This will work for every point in time you consider. If you consider many points at once, it will be too easy to fool yourself, by 1. misrepresenting some of the forces relative to others, and 2. leaving some out, both of which you are doing.
  9. So, again, how do you accelerate the thin ring without external forces on the straight part of the track? Just a note I have to add: You are applying Newtons Laws to something you have drawn, some geometry, some representation of a physical system. The result you are getting is an error in logic or in your assumptions. How can it be otherwise when you are basing it on Newton's laws alone and nothing else? You are not doing an experiment.
  10. With no outside forces, what accelerates the ring on the straight part of the track?
  11. Which comes back to: No, it doesn't work as described. If it did then congratulations, you are breaking known laws of physics, as what is described is impossible.
  12. Which momentum, angular or translational? You cannot add them together and each is conserved in an isolated system. Do not confuse them with kinetic energy. This is true. It has more kinetic energy. But no amount of energy can change the momentum (angular or translational) of an isolated system, unless it comes from outside the system, in which case it wouldn't be an isolated system.
  13. Merged post follows: Consecutive posts merged Same speed and more kinetic energy. So what? That had to be put in place as an input, as an initial condition. It's not a source of continuous energy and certainly doesn't empower it to break any laws of physics. Where are you adding the additional energy that you think you will get out of it? It's like claiming something heavier is a continuous source of mass, and how is that possible?
  14. OK. Only the variable moment of inertia flywheel can accelerate or decelerate without external inputs. The ring gains nothing by comparing it to a disc of equal mass any more than the disc would gain by comparing it to another disc of equal mass with an even smaller moment of inertia. (I won't get into the errors of the equal centripetal force claims despite the rings larger diameter as they are largely irrelevant) Now look at the acceleration and deceleration of the flywheel. Both in the same direction as you say, correct? Toward the faster end. (a momentum gain each time from the traction on the track) Now look at the change in velocity at the faster end. Assuming no track movement there is a full 180 degree shift in velocity at constant speed, from an acceleration, toward the slower end (a momentum gain each time from a force perpendicular to the track) This is opposite but greater than what happens at the other end, and exactly counteracts the momentum changes from the changes in speed at the midpoints. The flywheel "borrows" momentum from the track, all in the same overall direction at the slow end and both midpoints, and returns it all at the faster end. (it also 'borrows" angular momentum at one midpoint, and returns it at the other)
  15. I definitely will say for a fact that I have free will. (not that I have any choice in the matter )
  16. It might be hard for you to convince him of that. What is labeled "centripetal force" in the diagrams (correctly in the case of a static track) can do work if the track is free to move. Of course when that arises it changes the magnitude and direction of the centripetal force, (which as you correctly point out, does no work, but less strictly you could allow that it does), and the work is done by a component tangential to the path of the disc/ring/flywheel, as the track is displaced. Still nothing free, kinetic energy is lost by the disc as it is gained by the track, Conservation of energy is maintained at all times, Conservation of momentum is maintained at all times etc. (the thing doesn't work as described)
  17. Assuming an idealized system where the oval track doesn't move: It looks like the differences in the centripetal forces at either end of the oval are offset by the forces on the track that are not shown in the drawing during the acceleration/deceleration stages halfway between. Free to move unconstrained: All this system would do is wobble around without it's center of gravity changing velocity, with no net change in momentum, not even temporarily.
  18. I hate to quibble Martin, but I think this is a very restricted use of the term "reference frame". I think you can define a reference frame as you like and often there are advantages (or disadvantages) to doing so. I don't think I am using the term incorrectly. I would happily refrain from doing so if it is incorrect or even misleading as I think it is important to define our terms and speak a common language. If it is not obvious what frame of reference I'm referring to I try to qualify it. (rotating, inertial, or in this case expanding etc.)
  19. You might be right. Based on essentially nothing except that our current best is wrong, you could be right. Simple yet elegant on your part. I think you deserve a cookie.
  20. This is a good analogy. A flat map may not fit the whole Earth but "sea level" can be used as a preferred reference frame. It is pretty much flat everywhere locally, is a continuum of sorts etc. etc so to me it seems like the CMB isotropy frame (is there a better term- I have also called it the Big Bang Track) can be used as well. If the Universe , say, turns out to be a hypersphere, then it might be OK. If it was something very different it might lead to inconsistencies, but may still be more useful over greater distances than, say, an SR inertial frame.
  21. Thanks Martin. So we can consider all points that measure cmb isotropy to be in the same time frame, no matter how far apart, and no matter their relative velocities due to the expansion alone. Seems like a preferred reference frame.
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