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-   -   Generalized coordinates - Rotating pendulum (http://www.physicsforums.com/showthread.php?t=656707)

 assed Dec4-12 08:53 AM

Generalized coordinates - Rotating pendulum

My question is kinda simple but it has been causing me some trouble for a while. In the problem of the pendulum rotating about an axis, why isn't the angle of rotation about the axis a generalized coordinate? The doubt appears when i try to write the hamiltonian for the system and i don't know if i include the term relative to that angle.
How thats related to the fact that the angular velocity is or not constant.