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Everything posted by J.C.MacSwell

  1. Moontanman...come on...we all know you did it...just tell us what it was!
  2. Close on many counts...they were ordered from Canada...full of poutine... https://en.wikipedia.org/wiki/Poutine
  3. I think FatherTed straightened us out in that one:
  4. The motion of the centre of mass, of the m1/m2 system, cannot change in the x direction.
  5. Which one? The original one you claimed would continue to rotate, but would not, or the one with mass at m2 as well as m2 that would allow for rotation and oscillation at constant KE (assuming no friction or dissipative forces) with no extra energy to spare in doing so?
  6. Don't forget the cube square law as it relates to this model. The lift goes up with squaring of the scale but the weight, which tends with volume when it does well, goes with getting cubed. So a full size version won't respond the same way...you would have to fast forward the video.
  7. Interesting, but what's with the no stagnation point claim? It also has a pretty poor aspect ratio, so claims of efficiency are dubious. Pretty cool maneuverability though it is a small model. Looks like the proverbial UFO.
  8. That would of course depend on "h" the height of the fluid, but certainly true if h is more than 32 feet in height.
  9. It will move if released...but it won't come back...m1 will continue on it's track...unless acted on by a force. Massless m2 will follow. No force...no rotation of m1 about m2...no oscillation for m2. Compare with two balls joined by a string: Grip one and spin the other overhead then release. Now they fly off but neither in a straight line as they also rotate about the centre of mass. The string will be in tension keeping them together...supplying the necessary centripetal force for rotation.
  10. These are contradictory. If you had a ball on a string and you spun it overhead in a circle you would feel a centripetal force...if you released it so that it was "free to move" it would fly away in a straight line...being free to move it would no longer travel in a circle...as it is unable to "pull on the centre" of that circle. With no centripetal force their will be no centripetal acceleration...therefore no turning in a circle.
  11. How do you find it easy to imagine it rotating when/while it is unable to pull on the centre?
  12. In this case, with the pivot point oscillating in the x direction while at the same time angular velocity remaining constant, it would vary in any inertial frame. (there is one exception based on that statement...but it isn't claimed or happening...and just adding noise to describe it)
  13. In Seanie's description of the movement (which does not properly describe how the device would move), m1(the only mass in the system) would necessarily vary in speed...thus vary in KE.
  14. No. Setting aside the fact that the rod between the swinging mass (now m2, was m1) and the pivot point is now fixed in length, the fact that a second unfixed mass is in play will actually bring about some continued rotation, and x direction oscillation (or at least change in x component speed of the individual masses) So it can behave in a manner similar to how Seanie believes his/her device would behave. Without of course, generating any extra energy.
  15. When m2 is free to slide in the x direction...what supports the centripetal force when the rotating rod is aligned with the x axis?
  16. I think it would be helpful if you looked closely at the terms you are using, as they are applied in physics. http://physics.bu.edu/~duffy/py105/notes/Energy.html
  17. Yes. Some laws of course much more than others. Now compare this with impeachment. Much less precedence to go on...and many times the politics.
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