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Your Safer Source for Science
All-In-One Science Solution
Your Safer Source for Science
;
Address P.O. Box 219 Batavia, IL 60510
Phone 800-452-1261
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Email [email protected]
firewatch

When an oblong, boat-shaped object—known as a celt, rattleback or wobblestone—is rotated about its vertical axis in a particular direction, it will stop rotating, begin oscillating, and then spin in the opposite direction. Here’s how to construct your own mysterious celt from an ordinary spoon.

Concepts

  • Conservation of Energy
  • Rotational Motion
  • Inertia