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Homework Help: Interaction between two material points

  1. Jul 25, 2012 #1
    Hi,
    there are two material points with unitary mass that can move on a stright line. They are subject to a potential of mutual interaction V which depends on x and y and it's not symmetric, where x and y are the coordinates of the two points.
    I can choose in the istant 0 v1,v2,x and y. How can I find, in t=0, the force that x and y suffer because of the potential?
     
  2. jcsd
  3. Jul 26, 2012 #2
    I may have misunderstood the question, but if you have the potential field at every point, the force felt should be:

    [itex]F=-∇U(x,y)[/itex].

    F is the negative of the gradient of U

    to simplify even further, if you say the masses move on straight lies only, this becomes a one dimensional problem, as you can express y as a function of x.
     
  4. Jul 26, 2012 #3
    Yes, but x e y are coordinates along the same straight line.
    I might get the two forces by the derivative of the potential respect to x and y with changed sign, but if you look at how the system evolves at regular intervals, the mechanical energy is not conserved.
     
  5. Jul 27, 2012 #4
    up..
     
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