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Math Help - Vectors

  1. #1
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    Vectors



    The only other thing you need to know is the force T has a magnitude of 500N.

    I'm having trouble solving this. My process is as follows:

    • Find a unit vector in direction of C to E
    • Find components of T using the unit vector from C to E
    • Find vector r from B to C


    I then used the cross product of rBC x T, and am not getting the correct answer.

    I'm getting: 33.4i -124.98j - 183.43k (Nm)

    The answer is: -12.0i - 138.4j - 117.4k (Nm)

    Please help!
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  2. #2
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    B = (-.35,0,-2) and C = (0,.2,0) this means \bold{BC} = (0+.35)\bold{i}+(.2-0)\bold{j}+(0+2)\bold{k}.

    Same idea with \bold{T} which is (.2-0)\bold{i}+(.4-.2)\bold{j}+(-.1-0)\bold{k}.
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  3. #3
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    How do you get B = -.35i -.2k? On the diagram, B = .35i + .2k.

    Anyway, I know how to do that stuff. I'm just wondering why my answer is wrong - did I do the question the wrong way?
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