3A15.20 - Physical Pendula

Code Number:
3A15.20
Demo Title:
Physical Pendula
Condition:
Excellent
Principle:
Potential to Kinetic Energy, Simple Harmonic Motion
Area of Study:
Acoustics
Equipment:
Rigid Pendula.
Procedure:

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.

References:
  • Milentije Lukovic, Vanja Lukovic, Milos Bozic, Vojislav Vujicic, "Inexpensive Physical Pendulum with Arduino", TPT, Vol. 59, #6, Sept. 2021, p. 432.
  • Efstratios Kapotis and Chrysoleon Symeonides, "Learning from a Museum Exhibit: The Case of the 19th-Century Compensation 'Gridiron' Pendulum", TPT, Vol. 57, #4, Apr. 2019, p. 222.
  • Yaakov Kraftmakher, "Driven Pendulum: An Advanced Experiment", TPT, Vol. 56, #9, Dec. 2018, p. 636.
  • Yaakov Kraftmakher, "Computerized Physical Pendulum for Classroom Demonstrations", TPT, Vol. 43, #4, Apr. 2005, p. 244.
  • Paul Gluck, "Versatile Physical Pendulum", TPT, Vol. 42, #4, Apr. 2004, p. 226.
  • Francis X. Hart, "Solvering" the Physical Pendulum", TPT, Vol. 42, #3, Mar. 2004, p. 150.
  • Bruce Denardo, "Demonstration of the Parallel-Axis Theorum", TPT, Vol. 36, #1, Jan. 1998, p. 56.
  • John Sherfinski, "A Counterintuitive Physical Pendulum Lab", TPT, Vol. 35, #4, Apr. 1997, p. 252.
  • R.W. Robinett and P.E. Sokol, "Investigating Physical Pendula with K'Nex", TPT, Vol. 34, #7, Oct. 1996, p. 427.
  • C. Gregory Hood, "Note on a Physical Pendulum Experiment", TPT, Vol. 34, #6, Sept. 1996, p. 327.
  • Charles J. Reidl, Jr., "Moment of Inertia of a Physical Pendulum", TPT, Vol. 34, #2, Feb. 1996, p. 114.
  • John E. Carlson, "The Pendulum Clock", TPT, Vol. 29, #1, Jan. 1991, p. 8.
  • Bruce Denardo and Richard Masada, "A Not-So-Obvious Pendulum Experiment", TPT, Vol. 28, #1, Jan. 1990, p. 51.
  • John F. Goehl, Jr., "No Calculus Needed", TPT, Vol. 27, #7, Oct. 1989, p. 502. 
  • Rick Guglielmino and Tom Boyce, "The Search for a Harmonic Minimum", TPT, Vol. 27, #5, May 1989, p. 361.
  • Mario Iona, "The Physical Pendulum", TPT, Vol. 17, #4, Apr. 1979, p. 224.
  • Julius Sumner Miller, "Another Enchanting Thought", TPT, Vol. 17, #3, Mar. 1979, p. 152.
  • George Oleh Kolodiy, "An Experiment with a Physical Pendulum", TPT, Vol. 17, #1, Jan. 1979, p. 52.
  • L. C. Corrado, "The Meter Stick Pendulum", TPT, Vol. 12, #8, Nov. 1974, p. 494.
  • George W. Horton, "Some Laboratory Work With Physical Pendulums", TPT, Vol. 4, #2, Feb. 1966, p. 78.
  • H. Hauptfleisch, T. Gasenzer, K. Meier, O. Nachtmann, and J. Schemmel, "A Computer Controlled Pendulum With Position Readout", AJP, Vol. 78, #6, June 2010, p. 555.
  • John C. Simbach and Joseph Priest, "Another Look at a Damped Physical Pendulum", AJP, Vol. 73, #11, Nov. 2005, p. 1079.
  • Thomas B. Greenslade, Jr. and Aaron J. Owens, "Reconstructed Nineteenth-Century Experiment with Physical Pendula", AJP, Vol. 48, #6, June 1980, p. 487.
  • M-904: "Pendula - Torsion & Physical", DICK and RAE Demo Notebook.
  • Julius Sumner Miller, "Forces and Masses", Physics Fun and Demonstrations, p. 98.
  • Yaakov Kraftmakher, "2.2, Pendulum", Experiments and Demonstrations in Physics, ISBN 981-256-602-3, p. 84.
  • Robert L. Wild, "Several Pendulums", Low-Cost Physics Demonstrations, #42, p. 28. 
  • George W. Horton, "Some Laboratory Work with Physical Pendulums," Apparatus for Teaching Physics.
  • Robert Ehrlich, "8.3 - Period of a Physical Pendulum", Why Toast Lands Jelly-Side Down, p. 123 - 124.


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