3B22.40 - Standing Waves in a Rod

Code Number:
3B22.40
Demo Title:
Standing Waves in a Rod
Equipment:
6 foot aluminum rod, or metal yard stick.
Procedure:

Hold the metal yard stick on one end and shake up and down.  You should be able to show the fundamental frequency and the first overtone which will have a clear node visible at the end opposite your hand.  

You can hold the metal rod or ruler vertically from the end and give it a karate chop in the center.  You will clearly see the nodes as the rod or ruler vibrates.  

References:
  • Lawrence W. Panek, Demonstration of the First Overtone Transverse Vibrational Mode in a Stiff Solid Bar", AJP, Vol. 48, #9, Sept. 1980, p. 786.
  • Robert Ehrlich, "J.13. Resonant Standing Waves in a Rod", Turning the World Inside Out and 174 Other Simple Physics Demonstrations, p. 138 - 139.
  • Robert Ehrlich, "J.12. Transverse Waves in a Rod", Turning the World Inside Out and 174 Other Simple Physics Demonstrations, p. 138.

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