Kundt's Tube - Oscillator Driven

Purpose

To demonstrate standing waves in an air column.

Equipment

Kundt's tube with cork dust and rosin cloth.

Images

Description

An oscillator in the 1000-5000 Hz frequency range drives a loudspeaker at one end of a clear plastic tube, with the other end stopped by a moveable plunger. Varying the frequency of the oscillator or the position of the plunger, one can obtain a series of standing wave patterns, which are made visual by the motion of cork dust in the bottom of the tube. The standing wave pattern is shown to large groups by placing the device on anoverhead projector. This is a very dramatic demonstration, and is very effective in providing an introduction to standing sound waves. For elementary classes, the mot

References

Lecture Demonstration, Bill Norwood, Demonstration Design Drawing, (June 1978). ◙Specifications and Instructions for Models ID-40 and ID-40T Heavy Duty Drivers, University Speakers/Microphones, Oklahoma City, OK. E. N. Da C. Andrade, On the Groupings and General Behavior of Solid Particles Under the Influence of Air Vibrations in Tubes,Philosophical Transactions of the Royal Society of London, Vol 230, 13-445, (1931). A. T. Jones, Sound, 208-214, Van Nostrand, NY (1937). A. T. Jones, Sound, 172-180, Van Norstand, NY (1937). ◙Howard S. Siefert, A Miniature Kundt Tube, AJP 7(6), 421-422, (1939