- #26

- 890

- 39

You are asking for justification because ## \vec L_p = I_p \omega ## is valid only for fixed-axis rotation. Right?. If you meant set up ##\sum \tau_p = dL_p/dt ##and then show that##dL_p/dt = I_p \alpha##, then I'm with you. But if a student were to start with ##\sum \tau_p = I_p \alpha##, I would ask for justification since I don't think this equation is generally valid.