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What will be the reaction for current flowing in a wire ?

  1. Jul 10, 2010 #1
    Although some might think that this Q of mine is an inclination towards amateurism

    but yet this is what i want to know :)

    if every action has an equal and opposite reaction, then what will be the reaction for current flowing in a wire ?
  2. jcsd
  3. Jul 10, 2010 #2

    Doc Al

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    Re: Reaction

    When Newton's 3rd law talks about 'action/reaction' it is referring to forces between bodies. If body A exerts a force on body B, then body B exerts an equal and opposite force on body A. One of those forces is the 'action'; the other is the 'reaction'. (It doesn't matter which is which.)

    'Action/reaction' is sort of old fashioned terminology. Nowadays we speak of '3rd law pairs'.
  4. Jul 10, 2010 #3


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    Re: Reaction

    There is resistance to current flow. The EMF forces the charges (electrons) to flow, and the 'resistance' opposed the current.
  5. Jul 10, 2010 #4


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    Re: Reaction

    Big transformers in substations are designed for the turns to move as a reaction from the large magnetic fields produced by the surge current when switching in a big load.
  6. Jul 10, 2010 #5
    Re: Reaction

    Well i totally have consent to your post, but Mr. Newton proposed that the reaction should be equvalent to the action.
    Thats what giving me a thought, the equivalence to the flow?
    Which i could not think of?

    Probably i could find some one ellaborating that
  7. Jul 20, 2010 #6
    Re: Reaction

    so whats up

    any one here can solve the issue!!
  8. Jul 22, 2010 #7


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    Re: Reaction

    Current flowing in a wire is the 'reaction' to a potential difference 'action' between two points.

    Point A has a surplus of charge, and Point B has a deficit of charge, hence there is a difference in the potential energy. Current, otherwise known as dQ/dt or the movement of charge over a period of time, is a description of how the charged particles move from A to B, limited only in magnitude by the resistance of the medium.

    Reading into Conservation of energy, Ohm's Law and Kirchhoff Voltage/Current Laws should give you answers also.
  9. Jul 27, 2010 #8
    Re: Reaction

    well every thing work alright uptill it is in concern to opposition, but i cant work out about the equivalence of the two pair???

    confused !
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