In this acoustic experiment, two U-shaped glass tubes are connected by two flexible latex tubes of different lengths. Hold a struck tuning fork at the end of one of the U-tubes and the waves flow down to where the tubes divide. This apparatus makes the waves in one half of the fork in the U-tube travel half a wavelength farther than the waves in the other half of the fork. When the waves meet in the other U-tube, they’re in opposite phase to each other, so they cancel each other out. This results in no sound at all in perfect conditions. If you pinch closed one of the latex tubes, the sound will reappear.
This apparatus is supplied with enough rubber tubing to accommodate frequencies of approximately 200 Hz or greater. There is no sound generator included with this apparatus. We recommend using a tuning fork or any of the multiple tuning apps available for your phone. The most helpful thing to have is a sound generator that puts out a constant, known frequency.
WARNING: This product can expose you to chemicals including arsenic, which are known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information go to www.P65Warnings.ca.gov.
This product contains latex, which can cause allergic reactions in some people. If symptoms of an allergic reaction occur, stop use immediately and consult a physician.
Our products are not toys. Use in a laboratory or educational setting only. Not for children 13 and under.