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Homework Help: Relative motion in 1 and 2 dimensions

  1. Feb 8, 2005 #1
    can someone explain the concept of relative motion in one and two dimensions?
    how do i determine relative motion?
  2. jcsd
  3. Feb 9, 2005 #2
    Relative motion is the velocity an object is moving relative to somehting else.

    So for one dimension:
    If we have object A moveing in the -x direction with a velocity of -5 m/s and object B moving in the +x direction with a velocity 5m/s. If we wanted to know the relative velocity of A from B, it is the same as considering B still and A moving.

    To find the answer we subtract B's velocity vector from A's velocity vector.
    Avv -Bvv = -5m/s -(5m/s)

    Relative velocity of A from B:
    Avv -Bvv = -5m/s - 5m/s = -10ms

    Relative velocity of B from A
    Bvv-Avv = 5m/s -(-5m/s) =5m/s +5m/s) =10m/s

    The same can be extended to two dimentions by using two dimensional vectors.
  4. Feb 9, 2005 #3
    thanks i got it
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