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Homework Help: Find the direction and magnitude of the third force

  1. Sep 21, 2004 #1
    Can someone help me with this problem am clueless.

    An object acted on by three forces moves with constant velocity. One force acting on the object is in the positive x direction and has a magnitude of 6.5N; a second force has a magnitude of 4.4N and points in the negative Y direction. Find the direction and magnitude of the third force acting on the object?
  2. jcsd
  3. Sep 21, 2004 #2
    Since the velocity of the object is constant, the resultance of the three forces acting on the object is zero.
    If there would be a resulting force there would have been an acceleration. F=m*a remember?

    If you make a scetch with a dot representing the object and the 2 known forces as vectors you can see approximately where the third force would be and how big it is.

    Hopefully you can calculate it as well with these hints.
  4. Sep 21, 2004 #3
    Thanks Jovaro for your help
  5. Sep 21, 2004 #4
    so according to my understanding the third force has to be a total of 10.9 N in order for the resulant to be zero?and the direction is y positive and x negative
  6. Sep 25, 2004 #5
    Not really, take a look at the drawing. That should make it clear.

    Attached Files:

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