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Spinning Penny and Tray of Glasses

Learning about the science of centripetal force... and flying water!


Learning about Newton's Laws of Motion is anything but boring. Grab a clear balloon and a penny and learn about interia and centripetal force (that's right... it's centripetal - not centrifugal). Once you've mastered the Spinning Penny demo, you'll need to move Netwon's Waiter Tray - a spinning tray of glasses. As you'll see in this video, everything went just fine until the spinning waiter's tray accidentally hit the lady's leg... and then the demo turned into flying glasses of water!