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Vectors problem

  1. Jun 8, 2009 #1
    I ve got two questions.

    1. how to find the component of the force F in the direction of the displacement s?

    I have two vectors and angle between them.

    2. how to find moment of force F when applied at position r= 2a+7b-3c

    No idea how to start:(. Thanks for helping me.
  2. jcsd
  3. Jun 8, 2009 #2


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    Homework Helper

    1) It very much depends on the angle doesn't it? Then which axes you choose to determine he result. I usually choose the axes that make calculation the easiest - like along one of the vectors.

    2) Moment is r X F. Your interest then will be in the cross product between the displacement and the force.
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