Dynamics of masspoint collections

Home Physics Equations Classical Mechanics Dynamics of masspoint collections


The centre of mass
The velocity with respect to the centre of mass R is given by v-R The coordinates of the centre of mass are given by:
coordinates of the centre of mass

In a 2-particle system, the coordinates of the centre of mass are given by:
coordinates of the centre of mass for 2-particle system

With r=r1-r2, the kinetic energy becomes: , with the reduced mass given by:
reduced mass

The motion within and outside the centre of mass can be separated:




Collisions
With collisions, where B are the coordinates of the collision and C an arbitrary other position, holds: is constant, and is constant. The changes in the relative velocities can be derived from: changes in the relative velocities Further holds , = constant and L with respect to B is constant.