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Homework Help: Confused on vectors.

  1. Sep 18, 2012 #1
    1. The problem statement, all variables and given/known data


    2. Relevant equations

    x^2 + y^2 = r^2

    3. The attempt at a solution

    I understand everything, but the last segment.

    What vector B when added to vector A, gives a resultant vector with no x component and a negative y component 3.34 units in length?

    So 3.34 = Sqr Root [(0^2) + (y^2)]

    You get 3.34 again, and because it states the y component should be negative, I plugged in -3.34, but alas, it's wrong. -.-

    Ignore the 2.12 that I plugged in on the screenshot, I was just trying different ways of working this out.
  2. jcsd
  3. Sep 18, 2012 #2

    Doc Al

    User Avatar

    Staff: Mentor

    They want the j component of A + B to equal -3.34. Do your values for the j components add to -3.34? (Set up a simple equation and solve for By.)
  4. Sep 18, 2012 #3
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