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Vector addition and magnitude

  1. Feb 25, 2012 #1
    1. The problem statement, all variables and given/known data

    Vectors A and B have equal magnitudes of 10.0. If the sum of A and B is the vector 3.13j , determine the angle between A and B

    2. Relevant equations

    3. The attempt at a solution

    I gave both A and B the length r=10
    I don't know how to add them together if I dont know them.
    Please tell me where to start
  2. jcsd
  3. Feb 25, 2012 #2


    Staff: Mentor

    When you add two vectors you place the second on the tip of the first the addition is then the vector from the base of the first to the tip of the second. If you draw it out it's a triangle and since A and B have equal lengths then it's an isosolese? triangle.
  4. Feb 25, 2012 #3

    okay, which would make the angle 45 degrees?
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