PURPOSE: To demonstrate inertial forces in bodies submerged in air and in water.
DESCRIPTION: On one side of the arm a pingpong ball is suspended by a string from the top of a jar filled with air. On the opposite side of the arm a pingpong ball is attached by a string to the bottom of a jar filled with water. When the arm is rotated, the ball in the air jar moves outward and the ball in the water jar moves inward.
REFERENCES: (PIRA 1D52.30) See Demonstration Reference File for several interesting articles.
EQUIPMENT: As photographed.
SETUP TIME: None.
Go back to Lecture-Demonstration Home Page.