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PIRA Code(s)
Set up time
10 minutes
Physics and Science Concepts
Centrifugal force
Spin the frame and watch the two balls move outwards. For the plexiglass demo, squirt green liquid (or pour) into the frame so that the liquid is at least an inch deep. Then, plug in the cord.
Make sure objects and people are well clear of the spinning frame. Wear safety goggles during operation.

In one demo, a wooden frame with two curved tubes is situated on a turntable. As the frame is spun, centrifugal force causes the ball in each tube to move outwards and up the curve of the tube. The other demo shows the same concept. As the frame is spun , the green liquid in it moves towards the outer edges of the frame, also due to centrifugal force.