Is Angular Momentum Constant in the Body Frame of a Rigid Body?

[Ahmes]

It might be a stupid question but I do want to make sure of that:
Angular momentum of a rigid body (such as a disc) is a constant vector in the lab frame.
It is a vector in the body frame too, is it constant in the body frame?

I refer to simple bodies with 3D rotation such as a rotationg disc or a heavy top.

Thanks in advance.

 

[Ahmes]

I am truly a stupid person - in its own frame a body does not rotate - right?

 

[gandharva_23]

one can calculate the angular momentum about any point on the body and it will be different about any point . i mean if L1 is angular momentum about one point and L2 is angular momentum about any other point (both the points are on body) then L1 will not be equal to L2 . To calculate angular momentum about any point on the body just find the product of angular velocity of the body and the MOI about that point (think why!)