Wind Chime Project
Name:
Your task will be to design and build a wind chime based on a musical chord of your
choice. A chord is a harmonic combination of several notes. Each note is a sound wave
with its own frequency. As you know, the frequency of a note determines its pitch.
Notes with higher frequencies have higher pitches.
If a note has a frequency that is double the frequency of another note, the two notes are
said to be the same. For example, a note with a frequency of 220Hz is the musical note
“A”. A note with a frequency of 440Hz is also an “A” note. These two notes are said to
be one octave apart.
In western music, each octave is divided into 12 notes. Your first task will be to
determine the frequency for these notes. To do so, you must use the mathematical
relationship between frequency and note number. This relationship is:
Freq = (27.5)*2(x/12)
1. Complete the appropriate table using this relationship.
2. Measure the length of 4 or 5 copper pipes in centimeters. You may need to create
your own pipe lengths to do so. Use LoggerPro and the microphones to determine the
frequency for each of these pipes. In order for the pipe to resonate you must hold the
pipe 2/9 from the end of the pipe. Measure this distance carefully. Enter this data
into the proper table.
3. Using your calculator or Graphical Analysis, find the power equation that relates pipe
length (x-axis) to frequency (y-axis).
Power Equation:
y = A*(x)B
4. Choose a chord for your wind chime. Your wind chime should include between 4
and 6 musical notes. Select the notes for you wind chime from the proper table and
look up the frequencies for these notes. Choose notes so that the lengths of each pipe
are similar. Then, use your power equation to find the lengths of pipe that will give
you the proper frequency.
5. Find some pipe and start cutting. Cut the pipes to the lengths you have determined
will give you the sounds you have chosen.
6. You must now drill holes into your pipes. However, you do not want to affect the
frequency of your pipe when drilling these holes. Thus, drill your holes 2/9 of the
distance from either end of the pipe. This position coincides with a node (the position
on a standing wave that does not appear to vibrate).
7. Find the actual frequency for each pipe and compare this to what you intended the
frequency to be. Use these values to calculate the percent error.
8. You must now assemble your wind chime. First you must find something decorative
from which to hang your wind-chime. You must provide this yourself. Once you
have selected an object, obtain a clapper (the thing that hangs in the center of the
wind chime and bumps into the pipes when the wind blows) and some fishing line.
Sand and polish your pipes prior to assembly. Use your creativity when putting your
chime together. Make it something of which you would be proud.
9. Summarize your results in a one page, typed report. Be sure you turn in your data
tables with your summary. Your report should include the following.
 How did you determine the frequency of the pipes in step 1?
 How did you find the experimental power equation for frequency vs. length?
 How did you calculate the lengths of pipe once you determined the
frequencies of the notes you wanted in your chime?
 Why do you need to hold or hang a pipe 2/9 of the distance from either end?
 How did the actual frequencies of your final pipe compare with what you
wanted them to be? What caused these differences?
10. Complete a sketch of one of your tubes resonating. Label all significant parts.
Project (wind chime and summary) is due May 15
Musical Note Table
Note
Number
C
C sharp
D
D sharp
E
F
F sharp
G
G sharp
A
A sharp
B
C
C sharp
D
D sharp
E
F
F sharp
G
G sharp
A
A sharp
B
C
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
Frequency (Hz)
Length (cm)
880
1760
You only need to complete this table for the notes you plan to include as part of your
wind chime.
Power Function Table
Use this table to find the relationship between pipe length and frequency.
Trial
1
2
3
4
5
Length (m)
Frequency (Hz)
Write your power equation here:
Freq =
Results Table
Use this table along with the equations provided to determine the note
frequency and the pipe lengths. Then determine how closely your actual
frequency is to the intended frequency.
Note you
Selected
Note
Number
Pipe
Length
(m)
Intended Experimen
(Actual)
tal (Lab)
Frequency Frequency
(Hz)
(Hz)
Percent
Error (%)