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Can the angular momentum of anybody regardless of whether its symmetrical about the center of mass or not be found by finding the angular momentum about its center of mass and summing it up with the angular momentum of the center of mass?

(Here the angular momentum of the center of mass would be the angular momentum from your reference point if you consider that all the mass of the body is placed at the center of mass. (retaining the same angular velocity) and the angular momentum about the center of mass would be the angular momentum of the body with the center of mass as the reference point.)

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  • $\begingroup$ A related College level answer physics.stackexchange.com/a/91246/392 $\endgroup$ Commented Nov 4, 2014 at 14:20
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    $\begingroup$ The best way to ask a homework problem is to ask the specific physics concept you're struggling with. The way you've phrased the question, you haven't quite done that yet, but it shouldn't be a tough fix. Just try to edit in a concept about the problem that is causing you to struggle. What makes this problem different/more challenging than other angular momentum problems you solve? $\endgroup$
    – Sean
    Commented Nov 4, 2014 at 14:30
  • $\begingroup$ Also note your level with familiarity with vector algebra (vectors, matrices, cross products and rotations). All are skills needed to handle problems like this in general. $\endgroup$ Commented Nov 4, 2014 at 14:39
  • $\begingroup$ Fixed now? I think its more challenging because the object is not symmetrical about the axis through its center of mass. $\endgroup$ Commented Nov 5, 2014 at 13:37
  • $\begingroup$ What is the "angular momentum of the center of mass"? Please clarify the two parts of angular momentum proposed, maybe with an expression or example. $\endgroup$ Commented Nov 6, 2014 at 22:50

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I hope that you are familiar with the calculus with vectors. Then you can find the answer in Wikipedia, "Angular momentum in classical mechanics", the entry "Angular momentum simplified using the center of mass". I had a look at it right now, it is very simple and clear. You will find that, no matter if the object is symmetrical or not, you can do the calculus as you supposed.

Good luck,

Sofia

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  • $\begingroup$ If you find difficult to understand the equalities Σm_i R_i = 0 and Σm_i V_i = 0, ask me. $\endgroup$
    – Sofia
    Commented Nov 13, 2014 at 21:39
  • $\begingroup$ So whatever I heard about symmetry affecting the way we find the angular momentum of a body must be wrong? $\endgroup$ Commented Nov 14, 2014 at 12:33
  • $\begingroup$ What exactly you heard? The calculus in Wikipedia is general. Please be more specific about what seems to you problematic, or, give an example. $\endgroup$
    – Sofia
    Commented Nov 16, 2014 at 15:48
  • $\begingroup$ Someone told me the way of figuring out the angular momentum for asymmetric bodies is very different from the method you gave^ (they didnt mention what method though) $\endgroup$ Commented Nov 17, 2014 at 15:22

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