New Test of J.Nordberg's 'Field Reversing Sphere' Experiment

Discussion in 'Physics & Math' started by Q-reeus, Apr 2, 2013.

  1. Q-reeus Banned Valued Senior Member

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    Roll eyes indeed. Go rrright down to where it matters - fig's 11-19, 11-20, and the numberless fig. directly under fig. 11-20. Notice something odd? I mean compare to here:
    http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/magcur.html#c2
    Check to see if there is a publication date on or around April 1st.
     
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  3. Q-reeus Banned Valued Senior Member

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    Agreed. If of course he is contactable at all. I seem to recall RJB already tried emailing.
    Depends what you mean by needle. We've had this out and in #62. I explained that in order to take advantage of this purely hypothetical in vacuo magnetostatic curl B, a uniform bar magnet say must be pivoted other than through it's center. Well a compass needle is a 'bar magnet' hinged about it's center, so if one keeps thinking in terms of 'what would a compass needle do', wrong perspective is guaranteed.
    Actually I well understand theory behind conventional electric motors of various kinds. We are not dealing with anything like that here. Anyway this is a sideshow and I now regret 'spicing things up' back in #39, not imagining it would generate so much ongoing controversy. I suggest we agree to disagree and wait it out for test results to come in. If you wish to start a new thread on this matter then feel free. I recall coming across a rigorous analysis of energy exchange for a dipole subject to a finite curl (AC situation), but even if I found it again, the math may be too general or obscure to win any argument here.
     
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  5. Q-reeus Banned Valued Senior Member

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    Crossed-wires RJB - I was referring to Neddy Bate if you bother to check. He's the one having made a definite prediction. We two have an agreement, but I feel free to state the outcome is 99.99..% certain to be contrary to Nordberg. You knew my position on that well before we made the deal.
     
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  7. Motor Daddy Valued Senior Member

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    Maybe you mean compare to here

    Please Register or Log in to view the hidden image!

    http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/magcoi.html#c1

    The figure that you are talking about is a coil of wire, not a straight wire. Maybe you were born on April 1st?
     
  8. Tach Banned Banned

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  9. Motor Daddy Valued Senior Member

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    I was responding to Q-reeus' statement about the electricity PDF being wrong, or whatever he was trying to say.
     
  10. Q-reeus Banned Valued Senior Member

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    No, and you have obviously missed the obvious. Check the handedness rules, your ref. vs in my Hyperphysics link (and any other credible resource on basic EM).
     
  11. Motor Daddy Valued Senior Member

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    If it's so obvious just freakin' tell me! What is the problem with the PDF, specifically?
     
  12. Tach Banned Banned

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    Look at fig 11-19. Midway through the loop, the direction of \(\vec{B}\) is reversed. The text is correct, the drawing has a mistake. It is hard to see, since the drawing is so small.
     
  13. Q-reeus Banned Valued Senior Member

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    Got you a bit agitated it seems. I did say handedness rules. No savvy? Well even Nordberg got that right for a wire - using right hand, thumb points in direction of current flow, fingers curl in direction of field around that wire. Now go back and compare! Hell, the author there even calls it specifically 'the left-hand rule'. In which universe though?
     
  14. Motor Daddy Valued Senior Member

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    I think you're hallucinating. The arrows run in the same direction relative to the current flow the complete length of the loop. I don't see the arrows switching directions in the middle of the loop.
     
  15. Motor Daddy Valued Senior Member

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    Which direction is the current flow in a coil of wire that your thumb would point in that direction and the fingers would "curl" in the direction of the magnetic field???? I think you were a little too hasty to call BS!
     
  16. Tach Banned Banned

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    I think that I'm wasting time with you. But this isn't the first time.

    Time for you to get a new pair of glasses.
     
  17. Motor Daddy Valued Senior Member

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    If you were driving a car inside the loop, traveling in the direction of travel as the arrow indicates, the magnetic field would be circling counterclockwise the entire trip in that loop, and that is precisely what the diagram shows.
     
  18. Q-reeus Banned Valued Senior Member

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    Went back and doubled checked to make sure. Nope - the unknown author gets it all 'back the front' thanks to using his/her left-hand rule. Want to place a bet? (never used to like betting, but it pays here)
     
  19. Motor Daddy Valued Senior Member

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    You aren't even speaking clear enough to make your point to me. WTF are you talking about?
     
  20. Q-reeus Banned Valued Senior Member

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    Agitated again? Go back and read #110 again - I gave the correct rule for use with a straight length of current-carrying wire. Everything else follows from that - coils and what have you. You had the extraordinary skill to single out some truly odd article by some unknown - or can you hunt down the authorship perchance? Perhaps he/she's a roommate to Nordberg. :m:
     
  21. Motor Daddy Valued Senior Member

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    So I see you have a problem understanding the difference between a coil of wire and a straight piece of wire. Maybe you should redo Kindergarten to get some remedial training on shapes?
     
  22. Motor Daddy Valued Senior Member

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    Did you figure it out yet, Tach? You're awfully quiet now, and that usually means you are eating crow!
     
  23. Q-reeus Banned Valued Senior Member

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    4,695
    Ignoring that last insult, how do you figure I don't know the difference between coil and straight length? Point out where that can be shown - or retract.

    And you are yet to acknowledge yes or no on my observation your unknown author has it backwards in using a left-hand rule. So you agree or disagree?
     

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