PURPOSE: To demonstrat centripetal force and centrifugal reaction in a dramatic way.
DESCRIPTION: Balance the penny (face up) on the flattened coat hanger tip, as shown in the photograph. Start slowly swinging the hanger back and forth like a pendulum, then rotate it in a complete circle. With practice, it is possible to rotate the system several times and stop the motion without dislodging the penny.
REFERENCES: (PIRA 1D50.45)
EQUIPMENT: Bent coat hanger with flattened end, penny.
SETUP TIME: None.
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