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Intrinsic Angular Momentum

  1. May 25, 2010 #1
    Hi All,

    According to some text book, angular momentum can be represented as follows;

    L = rxP + I*W

    r is position from the origin, P is translational momentum, I is inertia tensor and W is angular velocity. Is it possible to call I*W part as intrinsic angular momentum?

  2. jcsd
  3. May 25, 2010 #2


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    Hi Barkan! :smile:

    (have an omega: ω :wink:)
    (where r is the position of the centre of mass, and I is the tensor about the centre of mass?)

    That's what I'd call it :smile: … but I don't know whether it's the accepted name.
  4. May 25, 2010 #3

    Meir Achuz

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    I think "intrinsic angular momentum" just refers to quantum mechanical spin, not classical rotation.
  5. May 25, 2010 #4
    yes tiny, symbols are referring the way you define.

    some people were criticizing me for using this term. the problem is how i am supposed to name I*W then? It is not 'angular momentum' because the term angular momentum includes other terms as written above. roy featherstone refers it as 'intrinsic' in his rigid body dynamics algorithm text book.

    any good ideas to name 'I*W' term?
  6. May 25, 2010 #5


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    Meir and those people have a good point.

    However, there ought to be a name for it, and "intrinsic angular momentum" does seem apt.

    The alternative is "spin angular momentum" or just "spin" (with the other component being "orbital angular momentum") … but "spin" also could be said to refer to quantum mechanical spin. :confused:
    I didn't know that … maybe it'll catch on? :smile:
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