Rattleback, 1M40.90
Topic and Concept:
Work and Energy, 1M40. Conservation of Energy
Location:
Cabinet: Mechanic (ME)
Bay: (A8)
Shelf: #1
Abstract:
A Toy that demonstrate energy conservation with rotational motion.
Equipment |
Location |
ID Number |
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Rattleback |
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Important Setup Notes:
- N/A
Setup and Procedure:
- Place Rattleback on table.
- Spin in one direction
- Spin in the opposite direction
- If Desired tap on either end to initiate spin.
Cautions, Warnings, or Safety Concerns:
- N/A
Discussion:
This Demonstration seems to violate the conservation of angular momentum but due to the asymmetrical shape of the Rattleback converts rotational energy in the non-preferred direction into an up-and-down rocking motion in both X and Y dimensions. This rocking energy is then converted into rotational energy in the preferred direction due to the imbalance of weight. This phenomenon would also occur when spinning in the preferred direction however at a much slower rate so that the dampening caused by friction stops the device before allowing the conversion to complete.
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