Linear discrete system, moment and center of mass
Three masses, represented as semicircles, are placed along the -axis. You can change each object's mass and location by moving the diamond-shaped point above the semicircle. Also, you can remove the mass by dragging the point below the -axis.
The moment of the system about the origin is calculated, and is represented visually as a spiral about the origin. The size of the spiral represents the tendency of the system to rotate about the origin in the presence of gravity.
The center of mass is indicated with a red on the -axis.