Where Is the Center of Mass of Florida?
An attention-grabbing center-of-mass demonstration uses the map of a state mounted on a sheet of heavy cardboard and cut out along the boundaries.1 The two-dimensional object is hung from a hole punched into a city near the edge, and a string with a pendulum bob attached to it passes through the center of mass. The process is repeated with a different city, and the center of mass is determined uniquely. I did this regularly with a map of the state of Ohio, and the geographic center of the state reliably came out to be the nearby village of Centerburg.
“Where is the Center of Mass of Florida?”, The Physics Teacher, 45, 359-360 (2007)
The Physics Teacher