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Homework Help: Vector Size

  1. Sep 22, 2010 #1
    1. The problem statement, all variables and given/known data

    Five vectors are listed below. Select them in order of increasing magnitudes, from shortest to longest. If B is smallest, then A, C, D, and finally E is the largest, enter BACDE (Note: If of equal length, then enter in the order listed.)
    A) 23i-31j-17k
    B) 36j+26k
    C) 43j
    D) 20i-34j-20k
    E) 30i+30j


    2. Relevant equations

    magnitude = sqrt (i^2 + j^2 + k^2)

    3. The attempt at a solution

    I found:

    A = 42.178

    B= 44.407

    C = 43

    D = 44.226

    E 42.426

    I ranked: AECDB or even follow the order list: AECBD => It's showing wrong???

    Could anyone explain what's going on? I'm really confused because I think I'm doing the right way!!!

    Thanks!
     
  2. jcsd
  3. Sep 22, 2010 #2
    As i see you squared the coordinates and took the root of their sum. Well thats the right way. probably some computation error. but the method is correct.
     
  4. Sep 22, 2010 #3
    Anyone has different ideas?
     
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