21.2: Translational Equation of Motion
( \newcommand{\kernel}{\mathrm{null}\,}\)
We shall think about the system of particles as follows. We treat the whole system as a single point-like particle of mass mT located at the center of mass moving with the velocity of the center of mass →Vcm The external force acting on the system acts at the center of mass and from our earlier result (Equation 10.4.9) we have that
→Fext=d→psysdt=ddt(mT→Vcm)