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Homopolar Electric Motor without wire connection

  1. May 22, 2012 #1
    Hey everyone,
    I came across this recently through a friend. I understand how a regular homopolar motor works, but I simply can't figure out how you get the copper wire sitting on top of the cathode of the battery to spin without a connection to the anode!

    I made a short video, please search "VsBePtKUyyw" on youtube, I can't post links yet.

    My main question is:
    Where and how does the current flow in order for the copper wire to experience a Lorentz force and start turning?

    When the magnet is attached to the anode or "- terminal" of the battery, the battery itself becomes a magnet. By placing a certain shaped copper wire on the cathode without completing the connecting to the anode, the wire begins to spin. I've looked everywhere and have not been able to find an example like this, all the other homopolar motors have a completed or loop wire connection from cathode to anode.
    Can anybody explain this without pasting links in here??
  2. jcsd
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