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An electromagnetic question.

  1. Nov 26, 2013 #1
    What are the three forces responsible for a neodymium magnet to fall slowly down through a heavy copper tube?
     
  2. jcsd
  3. Nov 26, 2013 #2

    Simon Bridge

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    Welcome to PF;
    That's a good question - what have you come up with so far?
    i.e. have you listed the forces that are available to the universe? There are only four - but I feel the question may be treating one of them as two.
     
  4. Nov 26, 2013 #3

    davenn

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    Hi clark

    its a good experiment, as Simon has said, have a think about what is happening
    A hint ... a moving magnetic field and a conductor :wink:

    also it could be any magnet and it works just as well with an aluminium tube

    I use this action to produce dampening in a seismometer ( earthquake detector)
    but rather than an aluminium tube, I use a moving strip of aluminium between 2 fixed magnets

    Dave
     
    Last edited: Nov 26, 2013
  5. Nov 26, 2013 #4
    Well I can think of the two obvious, Gravity and Electromagnetic force.
     
  6. Nov 27, 2013 #5

    Simon Bridge

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    1. gravitation
    2. electrical
    3. magnetic

    ruling out the strong and weak nuclear forces.

    But - it may be that the question is thinking in terms of a free body diagram?
    It really depends on where you are up to in your course.

    Have you tried davenn's suggestion?
     
  7. Nov 27, 2013 #6
    I know that an electric current is generated when the magnet moves through the conductor. I looked it up and found something called "Eddy's Current" that i will need to look into so i can better understand exactly what occurs.
     
  8. Nov 27, 2013 #7

    davenn

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    That's a good start :smile:
    Now think or research about what those eddy currents that are set up in the pipe do/cause


    Dave

    PS, note the little highlighted correction I did in your quoted text :smile:
     
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