Angular momentum finding the principle axis

AI Thread Summary
When determining angular momentum about the mass center of a cone rotating about its axis of symmetry, it is essential to recognize that the axis of symmetry is also a principal axis. The angular velocity does influence the angular momentum, particularly if the rotation occurs along a principal axis. To calculate angular momentum, one should first establish the angular velocity; if it aligns with a principal axis, the calculation simplifies to multiplying by the moment of inertia. If the rotation does not align with a principal axis, a tensor method is required for accurate evaluation. Understanding these principles is crucial for correctly analyzing the angular momentum in rotating systems.
SpartanG345
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If an object is rotating about the axis of symmetry
and you are trying to find the angular momentum about the mass centre g.

Does a rotation about the axis of symmetry correspond to a rotation about the principle axis?
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For this question i am trying to find the angular momentum about the mass centre of cone which is rotating about its axis of symmetry. However the axis of rotation is also rotating about the z axis.

Does the angular velocity w effect the angular momentum about the mass centre? I am guessing it would...

The only thing i am not sure about weather or not angular momentum about G would be evaluated about the principle axis
 
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Hi SpartanG345! :smile:

(btw, it's principal axis, like the principal of your school :wink:)
SpartanG345 said:
For this question i am trying to find the angular momentum about the mass centre of cone which is rotating about its axis of symmetry. However the axis of rotation is also rotating about the z axis.

Every axis of symmetry is a principal axis.

The principal axes of a cone are its centre line, and every direction perpendicular to that line.

To find the angular momentum, you must first find the angular velocity …

if that is along a principal axis, then just multiply by the moment of inertia; if not, then use the tensor method. :wink:
 
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