3C20.40 - Savart's Wheel-Musical Saws

Code Number:
3C20.40
Demo Title:
Savart's Wheel-Musical Saws
Condition:
Good
Principle:
Frequency of Sound Waves
Area of Study:
Acoustics
Equipment:
Piece of Cardboard, Musical Saws (4 Mounted on Same Axis), Motor-Driven Rotator, Electromagnetic Pick-Ups, 'Saw' Cog Wheel, and Amplifier.
Procedure:

Place the musical saw blades into the rotator and tighten securely. Start the motor and hold a piece of stiff cardboard against the rotating teeth and hear a different pitch for each set of teeth.

Plug the electromagnetic pickup into the Aux. input of an amplifier. Place the 'saw cog' wheel into the rotator, start and bring the end of the pickup close to the teeth and listen to the pitch vs. speed of rotation.

References:
  • Norihiro Sugimoto ( Stray Cats ), "Let's make "24:27:30:32:36:40:45:48" and Play Music", TPT, Vol. 58, #4, April 2020, p. 280.
  • Thomas B Greenslade Jr, "Apparatus Named After Our Academic Ancestors-II", TPT, Vol. 49, # 1, Jan. 2011, p. 28.
  • Sc- 2: Freier and Anderson,  A Demonstration Handbook for Physics.
  • S-121:  Richard Manliffe Sutton, Demonstration Experiments in Physics.
  • George M. Hopkins, "Experiments with the Scientific Top", Experimental Science, p. 173.
  • George M. Hopkins, "Sound", Experimental Science, p. 117.
  • Martin Gardner, "80, The Vibrating Card", Smart Science Tricks, p. 119.
  • "Frequency and Pitch",  Apparatus Notes,  p. 74.
  • Raymond Bruman, "Harmonic Series Wheel", Exploratorium Cookbook I, p. 66.1 - 66.9.




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