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Confused with the principles in Vector Moments - with Pictures

  1. Jun 27, 2011 #1
    Please use zoom function for better view.

    Untitled.png

    Untitled.png

    I'd highly appreciate it if you could also add a diagram on your explanation. Thanks!
     
  2. jcsd
  3. Jun 27, 2011 #2
    1.) Yes, the order does matter. As you correctly pointed out, you get a minus sign if you reverse the order of a cross product.

    2.) r, F and the resulting moment form a right handed system: http://en.wikipedia.org/wiki/Right-hand_rule . The moment is always orthogonal to r and F.

    3.) As pointed out in 2.), the moment is always orthogonal to r and F. The same is true for the rotational axis. Therefore the moment is parallel to the rotational axis.
     
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