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swansont last won the day on March 15

swansont had the most liked content!

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6766 Glorious Leader

About swansont

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    Washington DC region
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    Geocaching, cartooning
  • College Major/Degree
    PhD Atomic Physics Oregon State University
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  1. swansont

    Propellant less space engine

    Outside edge is in-line with the wheel. There is no asymmetry of speed with respect to that plane.
  2. swansont

    Propellant less space engine

    Which is true of both wheels, and is in-line with the rest of the disk. That doesn't move the center-of-mass upward. Plus, you would have to apply the equations, and not just hand-wave this, to determine the correct answer.
  3. swansont

    Mass/energy equivalence question

    Anything that is present due to an interaction with another particle or otherwise depends explicitly on position is configuration-dependent, as you note. If it doesn't, then it's not. Kinetic energy would be an example of an energy that is not (necessarily) configuration-dependent. In a system of particles that don't have long-range interactions, such as an ideal gas. It's more that conservation of energy includes mass energy, and mass is not a conserved quantity (though it's a reasonable approximation to say it's conserved at the macroscopic scale, in most cases)
  4. swansont

    Einstein in pre-Nazi Germany

    True. I had been under the impression these were solicited, but it's certainly possible it was just a collection of quotes/writings.
  5. swansont

    Einstein in pre-Nazi Germany

    From what I've read (and this may be wrong), there were not 100 essays in the book. Some authors are listed there without having provided any details of their disagreement. "Published in 1931, it contains short essays from 28 authors, and published excerpts from 19 more. The balance was a list of 53 people who were also opposed to relativity for various reasons." http://weeklysciencequiz.blogspot.com/2013/01/a-hundred-authors-against-einstein.html Do we know what the motivations are of people who only signed their name? The fact that there is apparently no overt anti-Semitism in the writings does not eliminate that as a motivation. The best you can say is "We don't know" regarding the motivation of over half of the people, unless they published critiques elsewhere and someone tracks them down.
  6. swansont

    Can have achieve nuclear fusion?

    That's not really the appropriate comparison. Fusion takes place in the sun's core, not the surface. It's much hotter in the sun's core. ————— Fusion in reactors is typically not p-p fusion as takes place in the sun. The reaction rate for that is really, really small (~billion year lifetime. It works for the sun because it's so big) Which means that some comparisons are not apples-to-apples (or protons-to-protons)
  7. swansont

    Mass/energy equivalence question

    Certain types of energy, such as potential energy, are dependent on the configuration. Energy and mass, not matter. Mass is a form of energy. Yes, mass will be a property of the configuration. If you have an electron and a proton, separated and with no KE, you will have a certain mass. If you combine them into a hydrogen atom, it must release energy (the PE goes down by 27.2 eV, and the KE goes up by half that amount). The Hydrogen has less mass in the amount of 13.6eV/c^2 If you absorb a photon with energy E and excite the atom, the mass will increase by E/c^2 These effects have been experimentally confirmed.
  8. swansont

    Propellant less space engine

    Perhaps I'm not understanding your diagram, but if the wheels gain mass, it happens all the way around the rim. Now you rotate the whole thing. I assumed, from your diagram, that it's the central axis that rotates. That adds another velocity vector, perpendicular to the existing ones. No change in the symmetry that I see to shift the mass vertically. And, as has been stated, you really need to do a careful analysis to ensure there's nothing weird about trying to exert the required torque, since the wheels are in a relativistic state, and you want to put the superstructure into one.
  9. swansont

    Questions About Mercury and Aluminum.

    ! Moderator Note I'm wondering why you newer folks don't just discuss this amongst yourselves, seeing as how you seem to be sharing computers.
  10. swansont

    Propellant less space engine

    But you have an imbalance in the wheel opposite it, so the system is symmetric. If there is an asymmetry, then a more detailed analysis is warranted. But, as Q-reeus has observed, things are not simple in these problems. Exerting a torque in such a system may involve a linear force as well, counterbalancing the possible mass shift. You have to actually do the physics if you want the answer.
  11. swansont

    Propellant less space engine

    I don't see an imbalance in your diagram. It's symmetrical. The outside edge is furthest from the center, and there is one on each side.
  12. swansont

    Banned/Suspended Users

    Vexen has been suspended for a combination of soapboxing and spamming. Far too many threads opened up with no further participation (and when participation is there, it is often of the category "tell me more"), and includes threads that are topics easily Googled. This is a discussion forum.
  13. swansont

    If I can imagine it, it is possible!

    Cookies are impossible.
  14. ! Moderator Note This is irrelevant to the discussion. Please stick to the topic.
  15. swansont

    Propellant less space engine

    Yes, it has more mass. There are very few situations where this would be the proper analysis. Is it? The object is moving. You can't analyze it in the rest frame of the object, since that's not the frame where you are analyzing conservation of momentum. You have asserted this. You have not shown this via analysis. That's not consistent with your setup, though, where everything is rotating n the same direction, so it's not really a simplified version. Not the same situation, though. The mass reads a greater amount in the first case because the extra mass is at one point on the wheel. The system oscillates. In the second, the extra mass is at the same point on the wheel. There is no oscillation. It's at steady state. This is functionally the same as the spinning top you referred to earlier. The mass is larger. That's it. There's no force it exerts on its own, resulting from that.