3A15.20 - Physical Pendula

Code Number:
Demo Title:
Physical Pendula
Potential to Kinetic Energy, Simple Harmonic Motion
Area of Study:
Rigid Pendula.

The rigid Pendula are used to show the characteristic differences of a pendulum that has the weight distributed through the length of the pendulum.

A simple pendulum with a length 2/3's of a physical pendulum will have the same period.  In our case a 66 cm long simple pendulum has the same period as our 1 m physical pendulum.

Theoretically, the physical pendulum will have the same period when swung from the end of the pendulum or from a point approximately 29 cm from the end.  In our case since the pivot point on the end is inward 1/2 cm, the other equal period point is at 32 cm from the end.

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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.