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Homework Help: Coulomb's Law and repulsion

  1. May 27, 2007 #1
    Actually, this is not a homework question, but more of a concept problem (Sorry I can;t follow the format). We are given that the force of repulsion or attraction between 2 charged objects can be represented by : Fe = (Kq1q2)/d^2. Does this mean that the sum of the force between both objects equals Fe, or is it that Fe represents the force felt by only one of the objects?
  2. jcsd
  3. May 27, 2007 #2
    What is newton's third law? ;-).

    Fe is the force that both of them feel because for every action there is an equal and opposite reaction.

    For example if you have a positive charge and a negative charge and you figure out that Fe = 200N, then the positive charge pulls on the negative charge with 200N of force. This means that the negative charge must also pull on the positive charge with 200N of force just as Newton's third law of motion says.

    Its the same as Fg(or any other force, I am just providing you with another example), if the earth pulls on you with 700N of force, then you pull on the earth with 700N of force as well.
    Last edited: May 27, 2007
  4. May 27, 2007 #3
    Ahh thank you. It makes a lot more sense to make the equation geared towards one object anyway :D
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