3A70.40 - Inverted Coupled Pendulum

Code Number:
3A70.40
Demo Title:
Inverted Coupled Pendulum
Condition:
Excellent
Principle:
Potential to Kinetic Energy, Simple Harmonic Motion
Area of Study:
Acoustics
Equipment:
Inverted Pendulum.
Procedure:

Use the special table clamp and get the pendulum so it stands straight up and down.  Gently start one of the pendulums in motion and within a short time the energy should be transferred to the other pendulum.  Increase coupling, may be done connecting the two pendulums together with a rubber band.  The closer the rubber band to the pendulum weights the greater the amount of coupling.

References:
  • Michael Thees, Sebastian Becker, Eva Rexigel, Nils Cullman, and Jochen Kuhn, "Coupled Pendulums on a Clothesline", TPT, Vol. 56, #6, Sept. 2018, p. 404.
  • Heather Stephens, Austin Tam, and Michael Moloney, "Decay Times and Quality Factors for a Resonance Apparatus", TPT, Vol. 49, #7, Oct. 2011, p. 421.
  • J. P. Sharpe and N. Sungar, "Supercritical Bifurcation in a Simple Mechanical System: An Undergraduate Experiment", AJP, Vol. 78, #5, May 2010, p. 520.
  • Ross L. Spencer and Richard D. Robertson, "Mode Detuning in Systems of Weakly Coupled Oscillators", AJP, Vol. 69, #11, Nov. 2001, p. 1191.
  • M. E. Oakes and Dean Creech, "Exposing Normal Modes", AJP, Vol. 45, #9, Sept. 1977, p. 882.
  • Freier and Anderson, "Sa-1", A Demonstration Handbook For Physics.
  • Freier and Anderson, "Mx-6", A Demonstration Handbook For Physics.
  • David Kutliroff, "71, Resonance Demonstrations with Pendulums", 101 Classroom Demonstrations and Experiment For Teaching Physics, p. 156.
  • Jearl Walker, "1.119, Coupled Pendulums", The Flying Circus of Physics Ed. 2, p. 58.
  • Julien Clinton Sprott, "1.18, Coupled Pendulums", Physics Demonstrations, ISBN 0-299-21580-6, p. 52.

 

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