In the example above, xcm = = = −8.
The system behaves as if an object with mass 8 kg were 8 units to the left of the
origin.
If the system consists of objects that are not confined to the same straight line, use
the equation above to find the x-coordinate of their center of mass, and the
corresponding equation
to find the y-coordinate of their center of mass.
If the net external force on the system is zero, then the center of mass will not
accelerate.
- Object A, of mass 5 kg, and object B, of mass 10 kg, hang from
light threads from the ends of a uniform bar of length 18 and mass 15
kg. The masses A and B are at distances 6 and 12, respectively,
below the bar. Find the center of mass of this system.