Rotator Apparatus

 

Code Number: 3B40.25

Demo Title: Doppler Effect - Rotator App.

Condition: Excellent

Principle: Doppler Effect on Sound Waves

Area of Study: Oscillations & Acoustics

Equipment: 

Reed on arm, Piezo Buzzer with battery on arm, Variable Speed Rotator, Wave generator, Amplifier, Speaker (small) on yardstick.

Procedure:

Make sure the rotators are in good shape. Tighten the desired arm securely and rotate at the desired speed.

CAUTION: Stay out of the way of the rotating arm when adjusting the speed. 

Plug the generator into the auxiliary input of the amplifier. Plug the speaker that is on the yardstick into the speaker outputs of the amplifier. Swing the speaker back and forth and listen to the Doppler shift.  

References:

  • Walter Schier, "Doppler Frequency Shift of Sound Apparatus",  TPT, Vol. 49, # 4, p. 246, April 2011. 
  • Marcelo M. F. Saba and Rafael Antonio da S. Rosa,  "The Doppler Effect of a Sound Source Moving in a Circle",  TPT, Vol. 41, # 2, p. 89, Feb. 2003. 
  • Herbert T. Wood, "Mechanical Analogue of the Doppler Effect", TPT, Vol. 30, # 6, Sept. 1992, p. 340.
  • V. Slusarenko, C. H. Worner, "Graphical Representation of the Classical Doppler Effect", TPT, Vol. 27, # 3, Mar. 1989, p. 171.
  • S. K. Chakarvarti, "The Doppler Effect: A Simple Analogy and Demonstration", TPT, Vol. 19, # 4, Apr. 1981, p. 320.
  • Donald E. Tilley, "Special Relativity and the Doppler Effect", TPT, Vol. 13, # 9, Dec. 1975, p. 560.
  • Vincent Mallette, "Doppler Effect Using A High Frequency Buzzer", TPT, Vol. 10, # 5, May 1972, p. 283.
  • Melvin Jones, "A Demonstration of the Doppler Principle", TPT, Vol. 13, # 2, Feb. 1975, p. 109.
  • An Zhong, "An Acoustic Doppler Shift Experiment with the Signal-Receiving Relay", AJP, Vol. 57, #1, Jan. 1989, p. 49.
  • L. Muldawer, "New Acoustic Doppler-Shift Experiments", AJP, Vol. 35, # 12, Dec. 1967, p. 1136.
  • W. Rovers and H. M. Skarsgard, "Demonstration of the Doppler Effect for Acoustic Waves", AJP, Vol. 35, #6, June 1967, p. 530.
  • Si - 3:  Freier and Anderson,  A Demonstration Handbook for Physics.
  • W- 380:  "Fork, Rod and Reed",  DICK and RAE Physics Demo Notebook.
  • Charles Vivian, "The Whistle and the Funnel", Science Experiments & Amusements For Children, p. 76.
  • David Kutliroff, "21, Doppler Effect with Sound", 101 Classroom Demonstrations and Experiments For Physics Teachers, p. 51.
  • Julien Clinton Sprott, Physics Demonstrations,  "3.5, Doppler Effect",  p.149, ISBN 0-299-21580-6.