BUILDING A MUSICAL BAND
Our goal this time was to design and construct 3 musical instruments that can play the notes: C, D, E ,F ,G, A, and B. a wind instrument, a percussion instrument, and a string instrument. With each of these models, we had to thoroughly explain how each one operated in relation to physics. After our research, we were to play our instruments to a song. Although due to lack of time our group did not finish our song.The instruments we built were a simple trumpet, a basic acoustic string instrument, and a xylophone.
Wind:
We created our wind instrument out of PVC pipe. We did some research and discovered the wavelengths of our desired notes. We divided those wavelengths by four because the vibrations create one fourth of a wave. So once we found the lengths we drilled holes in the PVC pipe so that the when you opened a hole the air traveled shorter distance making the note higher.
Note Frequency Length
C4 131.87 Hz 32.96 cm
D4 117.48 Hz 29.37 cm
E4 104.66 Hz 26.165 cm
F4 98.79 Hz 24.7 cm
G4 88.01 Hz 22 cm
A4 78.41 Hz 19.602 cm
B4 69.85 Hz 17.46 cm
C3 65.93 Hz 16.48 cm
We created our wind instrument out of PVC pipe. We did some research and discovered the wavelengths of our desired notes. We divided those wavelengths by four because the vibrations create one fourth of a wave. So once we found the lengths we drilled holes in the PVC pipe so that the when you opened a hole the air traveled shorter distance making the note higher.
Note Frequency Length
C4 131.87 Hz 32.96 cm
D4 117.48 Hz 29.37 cm
E4 104.66 Hz 26.165 cm
F4 98.79 Hz 24.7 cm
G4 88.01 Hz 22 cm
A4 78.41 Hz 19.602 cm
B4 69.85 Hz 17.46 cm
C3 65.93 Hz 16.48 cm
Strings:
To build our string instrument, we first found the tightness of the two strings necessary to produce a “C” note and a “D” note. To accomplish this, we had to take into consideration three things: tension, length, and thickness of the strings. After that, we took a plank of wood and attached a glass jar to resonate with the strings which amplifies the sound. The way sound waves reach our ears is in the the form of compressions and rarefactions in the air molecules. As the strings move back and forth, the air molecules are also moved at frequent intervals and when the alternating compressed and expanded molecules reach our ears as vibrations, the specialized receptors in our ears convert those vibrations to electrical currents which travel to our brain and are interpreted as sound.
To build our string instrument, we first found the tightness of the two strings necessary to produce a “C” note and a “D” note. To accomplish this, we had to take into consideration three things: tension, length, and thickness of the strings. After that, we took a plank of wood and attached a glass jar to resonate with the strings which amplifies the sound. The way sound waves reach our ears is in the the form of compressions and rarefactions in the air molecules. As the strings move back and forth, the air molecules are also moved at frequent intervals and when the alternating compressed and expanded molecules reach our ears as vibrations, the specialized receptors in our ears convert those vibrations to electrical currents which travel to our brain and are interpreted as sound.
Chimes:
To create our chimes we cut certain lengths of copper tubing. We decided on the lengths by researching how it would make the actual sound. The chimes work by vibrating and creating compressions and depressions in the air. The compressions and depressions in the air change due to the length of the tubing. To find lengths for the notes we cut a piece at a length to find what note it would create. The first note we found was that it was a G. After that we took ratios and multiplied it by the first length. The ratios should get us the notes after the G.We took the measurements and cut the the tubing, however we used a tubing that didn’t resonate very well. This made it hard to get the tubing tuned to the right note.
Ratios:
94%
89.5%
86.6%
81.7%
77.5%
73%
To create our chimes we cut certain lengths of copper tubing. We decided on the lengths by researching how it would make the actual sound. The chimes work by vibrating and creating compressions and depressions in the air. The compressions and depressions in the air change due to the length of the tubing. To find lengths for the notes we cut a piece at a length to find what note it would create. The first note we found was that it was a G. After that we took ratios and multiplied it by the first length. The ratios should get us the notes after the G.We took the measurements and cut the the tubing, however we used a tubing that didn’t resonate very well. This made it hard to get the tubing tuned to the right note.
Ratios:
94%
89.5%
86.6%
81.7%
77.5%
73%
PHYSICS CONCEPTS
Wavelength: The distance from crest to crest on a wave; measured in meters
Frequency/ f: How often a wave occurs; measured in Hertz (Hz). Frequency = 1/T
Period/ T: The amount of time between waves. Period = 1/f
Crest: The peak of a wave
Trough: The very bottom of a wave
Amplitude: The distance between either the crest or the trough to the middle of a wave
Wave speed/ Velocity: V = wavelength * frequency (in meters per second)
Transverse Wave: A wave that moves up and down as it moves
Longitudinal Wave: A wave that compresses as it moves
Constructive Waves: When two waves add together
Deconstructive Waves: When two waves subtract each other
Wavelength: The distance from crest to crest on a wave; measured in meters
Frequency/ f: How often a wave occurs; measured in Hertz (Hz). Frequency = 1/T
Period/ T: The amount of time between waves. Period = 1/f
Crest: The peak of a wave
Trough: The very bottom of a wave
Amplitude: The distance between either the crest or the trough to the middle of a wave
Wave speed/ Velocity: V = wavelength * frequency (in meters per second)
Transverse Wave: A wave that moves up and down as it moves
Longitudinal Wave: A wave that compresses as it moves
Constructive Waves: When two waves add together
Deconstructive Waves: When two waves subtract each other
REFLECTION
This was a very fun and useful project. The main theme that this project taught me was that things aren't always as easy as simple as they seem. This project was very very difficult and my group strugled a lot throughout the process. At first we had a hard time even designing our instruments, the calculations were very difficult but my team pulled it off. The construction was the easiest part, but after our final product was all finished I made the unfortunate mistake of playing our stringed instrument recklessly and i dropped it and broke the jar :( Although we bought some more jam and made like 20 pb&j sandwiches and got it all fixed, that was a major setback. To make our instruments better we could have had a better plan and better materials. Over all this was one of my favorite projects of the year because the final product was so satisfying.
This was a very fun and useful project. The main theme that this project taught me was that things aren't always as easy as simple as they seem. This project was very very difficult and my group strugled a lot throughout the process. At first we had a hard time even designing our instruments, the calculations were very difficult but my team pulled it off. The construction was the easiest part, but after our final product was all finished I made the unfortunate mistake of playing our stringed instrument recklessly and i dropped it and broke the jar :( Although we bought some more jam and made like 20 pb&j sandwiches and got it all fixed, that was a major setback. To make our instruments better we could have had a better plan and better materials. Over all this was one of my favorite projects of the year because the final product was so satisfying.