3B22.12 - Standing Waves in a String - Electrically Driven Tuning Fork

Code Number:
3B22.12
Demo Title:
Standing Waves in a String - Electrically Driven Tuning Fork
Condition:
Good
Principle:
Melde's Experiment
Area of Study:
Acoustics
Equipment:
Electrically driven tuning fork with an attached string, 0 to 20 VDC power supply, pulley/string tension device.
Procedure:

Set the device up much the same way as the other Melde's device (3B22.11).  Turn on the power supply to about 8 volts and adjust the point screw for a fairly large amplitude.  Adjust the tension device on the other end of the string until the desired number of standing waves in obtained.  NOTE:  too much tension on the string will stop the tuning fork.

References:
  • D. Rae Carpenter Jr.  "Letters: Impedance Matching with Speakers",  TPT, Vol. 30, # 9, p. 516, December 1992. 
  • John G. McCaslin, "Melde's Experiment Apparatus", TPT, Vol. 18, #1, Jan 1980, p. 69.
  • Sa-10:  Freier and Anderson,  A Demonstration Handbook for Physics.
  • W-270:  "Audio Oscillator Drives Wire",  DICK and RAE Physics Demo Notebook.
  • D. Colson, C. J. Lapp, J. A. Eldridge, "Experiment XXX*", 1936 Univ. of Iowa Physics Laboratory Manual, p. 37.

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