PrepZii

formula

Mass Moment and Discrete COM

The source starts centre of mass with mass moment and the COM of N discrete particles.

Mass moment

\vec M=m\vec r

Discrete system

\vec r_{cm}=\frac{m_1\vec r_1+m_2\vec r_2+\cdots+m_n\vec r_n}{m_1+m_2+\cdots+m_n}

\vec r_{cm}=\frac{1}{M}\sum_{i=1}^{n}m_i\vec r_i

$M$

total mass