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Can someone explain this can't understand notation

  1. Jan 6, 2010 #1
    from wikipedia for
    "The most general equation for rotation of a rigid body in three dimensions about an arbitrary origin O with axes x, y, z is"...

    i thought that the sum of the torques on a system is just equal to d/dt(L)=d/dt(Iw)...apparently not - but i can't understand the notation like, what is b, G..etc
  2. jcsd
  3. Jan 6, 2010 #2


    User Avatar
    Gold Member

    This article explains it better:

    I is the moment of inertia tensor
    ω is the angular velocity (a vector)
    ωq is the angular velocity about axis q.
    M is the total mass.
    bG/O is the vector from O to the body's center of mass.
    RO is the position of O.
    t is time.
    τO,j is one of the N moments about O.
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