3C20.16 - Ultrasonic Waves - Suspended Rods , Ultrasound
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.
- Thomas Allen, Alex Chally, Bradley Moser, and Ralf Widenhorn, "Sound Propagation, Reflection, and Its Relevance to Ultrasound Imaging", TPT, Vol. 57, #3, Mar. 2019, p. 134.
- Thomas B. Greenslade, Jr., "Marloye's Harp and the Thumb Piano", TPT, Vol. 39, #5, May 2001, p. 310.
- Thomas B. Greenslade, Jr., "The Acoustical Apparatus of Rudolph Koenig", TPT, Vol. 30, #9, Dec. 1992, p. 518.
- Thomas B. Greenslade, Jr., "Tonometers", AJP, Vol. 75, #6, June 2007, p. 574.
- Sf-4: Freier and Anderson, A Demonstration Handbook for Physics.
- David Goertz and Kullervo Hynynen, "Ultrasound-mediated Drug Delivery", Physics Today, Vol. 69, #3, Mar. 2016, p. 30.
- Johanna Miller, "Ultrasound Resolution Beats the Diffraction Limit", Physics Today, Vol. 69, #2, Feb. 2016, p. 14.
- William D. O'Brien Jr, Floyd Dunn, "An Early History of High-Intensity Focused Ultrasound", Physics Today, Vol. 68, #10, Oct. 2015, p. 40.
- Stanislav Emelianov, Pai-Chi Li, Matthew O'Donnell, "Photoacoustics for Molecular Imaging and Therapy", Physics Today, Vol. 62, #5, May 2009, p. 34.
- E. Carr Everbach, "Medical Diagnostic Ultrasound", Physics Today, Vol. 60, #3, Mar. 2007, p. 44.
- Frederick Kremkau, "Seeing is Believing? Sonographic Artifacts", Physics Today, Vol. 60, #3, Mar. 2007, p. 84.
- Jearl Walker, "3.25, Bat Finding a Flower", The Flying Circus of Physics Ed. 2, p. 156.
- Jearl Walker, "3.24, Bat Finding an Insect", The Flying Circus of Physics Ed. 2, p. 156.
- Julien Clinton Sprott, "3.10, Ultrasound", Physics Demonstrations, ISBN 0-299-21580-6, p. 169.
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