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Homework Help: Adding Vectors

  1. Feb 18, 2007 #1
    http://img366.imageshack.us/img366/5171/phwq5.jpg [Broken]


    Hello there. In lab, we measured vectors. I'm having a little concern on how to get X and Y. If I follow the books method, R_calc comes out too small compare to measure R. (Big % error).

    X:
    15.5+12.4cos37 = 25.4
    Y:
    0+9.3sin37 = 5.4
    R:
    square root of (25.4^2+5.4^2) = 26cm


    If I do it my way, R is a lot closer to measure.

    X:
    15.3+12.4= 27.9cm
    Y:
    0 + 9.3 = 9.3 cm
    R:
    square root of (27.9^2+9.3^2) = 29.4 cm


    The measurements (x1/2; y1/2; R m) are pretty accurate. What am I doing wrong? Thanks for any help.
     
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Feb 18, 2007 #2

    hage567

    User Avatar
    Homework Helper

    OK, I will try to point out a couple of things:

     
    Last edited by a moderator: May 2, 2017
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