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Homework Help: Resultant Help

  1. Mar 4, 2004 #1
    A 60-N force is acting at 30° east of north and a second 60-N force acting in the direction 60° east of north are concurrent forces. Determine the resultant of the forces.

    Using the Law of Cosines:
    c=115.91 N for the magnitude of the resultant

    Then, for the direction, I have no idea what to do.

    Can someone check what I have done so far and explain how to get the direction? Thanks...
  2. jcsd
  3. Mar 4, 2004 #2
    I've always liked to separate 2d vectors into 1d components, which then add nicely and algebraically. But to keep in line with your method, the next step would be to use the law of sines.

    [tex]\frac{\sin A}{a} = \frac{\sin B}{b}[/tex]
    where A is the angle opposite side a and B is the angle opposite side b.

    But if you do it this way, be sure to draw a picture! You'll need to add something to the angle you get to get it to work out properly.

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