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I Repelling Neutral Objects

  1. Aug 15, 2015 #1

    Positive charges atract negative charges, and repel positive ones.
    Same thing happens with negative charges.
    But both of them atract Neutral Charges.

    Is there any way for any charge to repel a neutral object?

    If it is, then is it possible to build any device that uses that kind of knowlegde to repel any object with a big force when triggered?
  2. jcsd
  3. Aug 15, 2015 #2


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    No they do not. A neutral charge does not experience any electromagnetic force.
  4. Aug 15, 2015 #3
    Well but isn't it possible to build something that repels any kind of object?
    Isn't there a force, a radiation something?
    Magnetic force is a possibility but to make it repel metal that it's not magnetized, the magnetic field would need to be on a constant destabilization.
  5. Aug 15, 2015 #4


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  6. Aug 15, 2015 #5
    I'm not sure what you mean by a repulsive force.
    Are you looking for something like 'anti-gravity', which could exert a force on *any* object, thus accelerating it, without actually being in contact with it?
    Electromagnetic effects, as you pointed out, can only apply to objects which have a magnetic field.
    Gravity appears to only work as an attractive force.
    That leaves the strong and weak nuclear forces, and I can't think how those might provide such a mechanism.
    Last edited: Aug 15, 2015
  7. Aug 15, 2015 #6
    Yes the solar sail *might* fall into this category, but it's basically just transferring of momentum isn't it?
    In principal the same thing as accelerating a ball by hitting it with a bat.
  8. Aug 15, 2015 #7
    I mean if it's possible to create a force field where objects that come with a certain speed can be stopped or slowed by entering that same force field, it may seem to much fiction, but i believe that it is possible.
    In other words, it's repelling objects that come near the same force we are talking.
    A magnetic force on non magnetized metals is the most obvious but it only works on metals that can be affected be magnetism.
    I wanted something that could maintain all kinds of objects away.
    Indeed a stable atmosphere inside that force field is possible since that same force field could not affect the lighter atoms like Oxigen, Carbon and Hidrogen.
  9. Aug 15, 2015 #8
    It does seem very much like you are seeking for something like negative gravity.
    I think that implies you would need to have a substance with a negative mass! - which is very exotic matter to say the least of it.
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