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Homework Help: Vectors and Work[Solved]

  1. Sep 23, 2009 #1
    A constant force F = -7i - 6j - 9k moves an object along a straight line from point (-3, 3, -3) to point (-3, 0, 5).

    Find the work done if the distance is measured in meters and the magnitude of the force is measured in newtons.

    So basically I know I need to do a dot product of F with the vector between the two points, but I keep doing my math wrong.

    Vector between points lets call them Po (-3,3,-3) and P1 (-3,0,5)
    I found to be (0,-3,8)

    So I then did the dot product between F and the Vector between Po and P1
    I got -90, but my answer is wrong?
    Last edited: Sep 23, 2009
  2. jcsd
  3. Sep 23, 2009 #2
    Re: Vectors and Work

    Ahah a foolish negative mistake thanks for looking guys, but I found the answer
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