 More Practice with Resonance in Pipes Printer Friendly Version
Describe the requested waveforms using "A" for an antinode and "N" for a node. For example, the fundamental in an open pipe would be expressed as "A N A" and the fundamental in a closed pipe would be expressed as "N A." Practice on your papers sketching the waveforms so you can become familiar with their constructions.

Open Pipe: Closed Pipe: The next two questions share common information.

 Describe using "A N" notation the waveform for the lowest frequency that can be played on an open pipe that is 55 cm long.

 Using the fact that the speed of sound equals 341 m/s, calculate the numerical value of the lowest frequency that this pipe can sustain.

The next three questions share common information.

 Describe using "A N" notation the waveform for the next to the lowest frequency that can be played on an open pipe 75 cm long.

If the speed of sound is 342 m/sec, calculate the numerical value of this frequency.
 What would be the frequency of the 5th harmonic in this pipe?

Refer to the following information for the next four questions.

Sound travels at 336 m/s in a 35.0-cm pipe with a closed end.
 Describe using "A N" notation the waveform for the fundamental frequency on your papers.

True or False? The fundamental frequency in this pipe would be 246 hz.
 Describe using "A N" notation the waveform for the 1st and 2nd overtones on your papers.

True or False?  The resonance frequencies of the 1st and 2nd overtones in this pipe would be 492 hz and 738 hz.
Refer to the following information for the next two questions.

An open organ pipe has a length of 0.75 meters. Room temperature is 26ºC.
What should be the length of a second, closed organ pipe if its second overtone is to match the fundamental frequency of the original, 0.75 meter-open pipe?

This question requires four steps to complete.
1. Determine the speed of sound in dry air when the temperature is 26ºC.
2. Determine the fundamental wavelength in a 75 cm-long open pipe.
3. Determine the wavelength, in terms of L, for the 2nd overtone (or 5th harmonic) in a closed pipe.
4. Set the required wavelength in Step 3 equal to the fundamental wavelength in Step 2 and solve for L.
 What is the common frequency of these two pipes?

Refer to the following information for the next question.

A tuning fork with a frequency of 528 hz is held above a resonance tube partially filled with water. The temperature of the air in the tube is 15 ºC.
 How far below the top of the tube will the water level have fallen when the tube first "sings" or resonates at the same frequency as the fork?  Related Documents