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Determining pole orientation

  1. Feb 2, 2009 #1
    Hello again everyone,

    I'm in the process of winding/sourcing out coils to produce induced flux of one or the other pole orientation. I understand that when a coil is induced by a permanent magnet the resulting force will be opposite and equal to the force that caused it. So if one induces the coil with the positive end of the magnet it will induce a positive field and vise versa. But, does the direction of the coil winding in a single closed loop coil, lets say clockwise, result in a positive pole or a negative pole, or is it the current flow that would determine pole designation? I know that when a cylindrical coil is induced by the positive side of a permanent magnet, the opposite end of the coil will automatically be the opposite. But what is not clear is, in the case of levitating trains (Inductrac) a figure of eight coil is used to keep the vehicle centered on the track. If I understand this correctly the first part of the loop is induced, by the passing train, which results in an opposite pole in the second part of the figure of eight loop. So, the current is traveling in a clockwise direction in the first part of the loop and counterclockwise in the second part of the loop, giving way to opposite poles produced from the initial pass. Am I looking at two separate issues here?

    Thanks everyone
  2. jcsd
  3. Sep 24, 2011 #2
    Well, it's been a while and thanks for all that read my post. The original post may suggest that I need to do some reading/experimentation on the subject, hence no responses to the post. Through experimentation I have found that there is a way to have a coil repell or attract a permanent magnet. What I needed was to have the magnet repell each time the current is turned on. But, having the core material an iron nail would only attract the magnet when the magnet is in the starting/stationary position, this wasn't going to work for my application. Although in my newly designed core, which still includes the iron nail, the magnet is still attracted to the nail in the starting position but now when I turn the current on the magnet repells, unlike the previous setup.

    Again thanks all for your reads.
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