3B22.14 - Standing Waves in a Wire

Connect the wave generator directly to the wire, and amplify the signal if necessary.  Or, you can also use the Mechanical Oscillator.  Run an AC signal of low frequency ( 0 to 1000 Hz.) through the wire or Oscillator.  As a magnet is brought near one end of the wire, standing waves will appear.  Adjust the frequency or wire tensions to achieve maximum amplitude.
Code Number:
3B22.14
Demo Title:
Standing Waves in a Wire
Condition:
Good
Principle:
Standing Waves
Area of Study:
Acoustics
Equipment:
Stretched wire, Magnet, Wave Generator, Amplifier or Mechanical Oscillator, Mass Set.
Procedure:

Connect the wave generator directly to the wire, and amplify the signal if necessary.  Or, you can also use the Mechanical Oscillator.  Run an AC signal of low frequency ( 0 to 1000 Hz.) through the wire or Oscillator.  As a magnet is brought near one end of the wire, standing waves will appear.  Adjust the frequency or wire tensions to achieve maximum amplitude. 

References:
  • Ray Scott Wakeland and Bennet Brabson, "Wave Speed on a String Revisited", TPT, Vol. 28, # 1, Jan. 1990, p. 57.
  • J.W. Jewett, J.V. Spadaro, "Vibrating String Resonance Spectra on the Oscilloscope", AJP, Vol. 50, # 6, June 1982, p. 570.
  • H. G. Hornung and M. J. Durie, "Stiffness Corrections for the Vibration Frequency of a Stretched Wire", AJP, Vol. 45, # 10, Oct. 1977, p. 991.
  • J. Morris Blair, "A Variaiton on Melde's Experiment", AJP, Vol. 38, #11, Nov. 1970, p. 1317.

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