Ultrasonic Waves - Suspended Rods





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 Code Number :   3C20.16

Disclaimer:

Reprinted by permission of Dick Berg, University of Maryland, for use on this website.

The demonstrations contained and referenced herein are listed for the purposes of cataloging and describing physics demonstrations which should be conducted only under the direction of a trained instructional support professional or physicist. These demonstrations are not presented for the purpose of being conducted by persons unconnected to this Facility and/or persons not consulting with or being supervised by the recognized instructional support professional or physicist and his/her staff. The University is responsible only for those demonstrations carried out using its own equipment using established safety and scheduling policies, and bears no responsibility for those choosing to use this source material for their own purposes. All demonstrations described and contained herein are public domain, and can also be found in reference materials in libraries, bookstores, and electronic sources.

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Condition :   Good  
Principle :   Audible Frequency Range of the Human Ear   
Area of Study :  Acoustics, Biology  
Equipment :   Two sets of ultrasonic rods and a striker.
Procedure :   Strike the rods on the end with the striker.  The shortest rod should have a frequency of 30 KHz which is well above the human range of hearing.  The longest rod should be within the range of human hearing.  With this set the limits of audition can be tested.

A microphone on the oscilloscope can be used to show that sound is still emitted from the bars that you cannot hear.

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   References

Thomas B. Greenslade, Jr.,  "Marloye's Harp and the Thumb Piano,"  TPT, Vol. 39, # 5, p. 310, (May 2001).

Thomas B. Greenslade, Jr., "The Acoustical Apparatus of Rudolph Koenig", TPT, Vol. 30, # 9, Dec. 1992, p. 518.

 

Sf- 4:  Freier and Anderson,  A Demonstration Handbook for Physics.

 


Mail Questions and Comments to:  Dale Stille