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PIRA Code(s)
Set up time
1 minute
Physics and Science Concepts
Rotational Dynamics, Centrifugal Force, Oblation
Place the shaft of the device into the hole and tighten the screw. Then, plug in the motor and turn on the red switch. When spun, the hoops will show oblation, the balls on the governor will move outwards, and the liquid in the glass sphere will move to the edge of the sphere.
Wear goggles when running the apparatus and keep hands away from the belt.

Centrifugal hoops and governor, when rotated, will show oblation. The balls on the governor will move outwards and compress the spring as the governor is rotated. The centrifugal force that supposedly causes this is actually due to inertia, and explains why the earth and other planets have a slight bulge around the part that rotates fastest. The rotational motor can also be used with a glass sphere partially filled with a colored liquid. When the sphere is spun, the liquid will rise along the inside edge of the sphere due to centrifugal force.