NEWTONSCRADLE
Newton's cradle
Newton's cradle, named after Sir Isaac Newton, is a device that demonstrates conservation of momentum and energy via a series of swinging spheres. When one on the end is lifted and released, the resulting force travels through the line and pushes the last one upward. The device is also known as Newton's balls or "Executive Ball Clicker".The above text is a snippet from Wikipedia: Newton's cradle
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