1M40.91 - High Bounce Paradox - Hopper Popper, Jumping Pencil, Slap Bracelet, etc.

Code Number:
Demo Title:
High Bounce Paradox - Hopper Popper, Jumping Pencil, Slap Bracelet, etc.
Energy Conservation
Area of Study:
Hopper Poppers.

Turn the hopper popper inside out and drop onto the table top.  When the popper hits the table it will revert to its initial shape and this release of energy will allow it to bounce much higher than the height it was dropped from.

The "Slap Bracelet" is another device that has some stored mechanical energy that is released when the straight metal piece is triggered and it curls around the wrist or around itself.

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Disclaimer: These demonstrations are provided only for illustrative use by persons affiliated with The University of Iowa and only under the direction of a trained instructor or physicist.  The University of Iowa is not responsible for demonstrations performed by those using their own equipment or who choose to use this reference material for their own purpose.  The demonstrations included here are within the public domain and can be found in materials contained in libraries, bookstores, and through electronic sources.  Performing all or any portion of any of these demonstrations, with or without revisions not depicted here entails inherent risks.  These risks include, without limitation, bodily injury (and possibly death), including risks to health that may be temporary or permanent and that may exacerbate a pre-existing medical condition; and property loss or damage.  Anyone performing any part of these demonstrations, even with revisions, knowingly and voluntarily assumes all risks associated with them.