1F20.10 • Inertia of Rest: Inertia Ball

Location: Cabinet 1

Photo Shows the Demonstration Used by the University of Texas at Austin.

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Instructions / Notes:

• A thin string is attached to a heavy steel ball, a metal bar/rod is attached to the other end of the string so that you can pull on it.
• If you slowly lift the ball with the metal bar, the string should not break.
• If you quickly jerk upward on the string, the string will break.
• Have the students guess where the string will break.
• Steel ball is about 6 cm in diameter and weighs about 1150 g.

Illustration is by Courtesy of the University of Minnesota.

Last updated on February 24, 2025