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PHY111 Vector sum questions

  1. Aug 29, 2009 #1
    1. The problem statement, all variables and given/known data

    vector a = 100 units at 50.0 degrees vector b = 200 units at 270 degrees. find r, sketch a,b, r.

    3. The attempt at a solution

    The part I don't understand is the 270 degrees. Doesn't this cause vector b to lay on the -y axis? I've tried this question and another one like it:

    vector a = 10 units at 40 degrees and vector b = 25 units at 180 degrees.

    Answers given for

    #1: 139 units at 62.4 degrees or 139 units at 297.5 degrees
    #2: 18.5 units at 20.4 degrees above -x axis, or 18.5 at 159.7 degrees

    This is the first physics class I have ever taken in my life. Help is greatly appreciated!
  2. jcsd
  3. Aug 29, 2009 #2
    nevermind, I found a similar question and was able to solve this!

    If anyone finds my question:

    Bx = 0
    By= -200

    That should help with the equation.
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