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Homework Help: Angle of two forces

  1. Apr 17, 2010 #1
    1. The problem statement, all variables and given/known data
    Not a specific question really.
    How would i find the angle of 2 combined forces in 2 dimensional motion. I have the the net force and the forces applied on both the x and y axis
     
  2. jcsd
  3. Apr 17, 2010 #2
    one way is to find the angle of each force with respect to an axis (x-axis for example), then from there you can do the rest job in finding the angle between them..
     
  4. Apr 17, 2010 #3
    k i don't really get what you mean so here is the question:

    Jack exerts 30 N and Michael exerts (cos 45 * 40) N at x direction.

    the net for is calculated by:
    30 N + (cos 45 * 40) N = 58.3 N. [E]
    0 N + (sin 45 * 40) N = 28.3 N. [N]

    I cant get the square root to work but you would use the Pythagorean theorem to get 64.8N of total net force

    (58.3)2 (28.3)2
    I don't know what to do to figure out the angle of the combined forces
     
    Last edited: Apr 17, 2010
  5. Apr 17, 2010 #4
    now you got a new force .. This forced originally was the resultant force of two forces , you can forget about this now ..

    Deal with the question as follows:

    You have a force of Fx=58.3N, and Fy = 28.3 (assuming that your calculations are right) .. Now find the angle as if you are dealing with this situation ...

    Hint: what is tan(theta) ...
     
  6. Apr 17, 2010 #5
    ok ok i got it now its just some simple trig from here thank you
     
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