Sound Waves Interference Essay

For this lab you are going to try to do an sonic double slit experiment and try to determine the wavelength of a sound wave.

1. View the videos below.
2. Open the link for a webpage to generate a pure tone sound on your phone at Sound Generator
3. Set the value at 343 Hertz. Since sound waves move at approximately 343 m/s this will produce waves of 1 meter wavelength. Play it at a comfortable low volume for you to year.
4. Now get a SECOND phone or computer and set up the sound generator as you did in step 2 before.
5. Change the frequency on one of the phones to 348 Hertz and listen for the classical beat frequency. You should hear a kind of “wa-wa-wa-wa” sound five times a second. The difference between the two frequencies.
6. Change the 348 value up and down by one Hertz at a time and notice how the beat frequencies changes. This is how musical instruments are tuned. When the beat sound is not longer heard then the instrument is in tune.
7. Change your setting for both phones to 3430 Hertz. This will produce a wound with a wavelength of .1 meters.
8. Place your phones one meter apart. If possible place them standing up facing you but this is not required.
9. Now place yourself about one meter away from the center of the phones a move in a line parallel to the phones. You should hear the sound getting louder and softer in as you do. This is the wave interference pattern occurring.
10. If possible it is best to try this in a big room or outside as inside the waves can bounce off the walls and produce a false signal.
11. Estimate the distance your head moves between between one loud sound and the next one. This is the the interference between the waves occurring. Call this distance y$y$.
12. As shown in class use the formula λ=(1meter)sin(tan−1(y1))$\lambda =\left(1meter\right)\sin ({\tan }^{-1}\left(\frac{y}{1}\right))$ to see how close you got to .1 meter. As the experiential method here is approximate the error maybe large. That is ok just state the values that you got.
13. Change the values on the phone to 1715 and repeat steps 9 and 10 to estimate the wavelength.
14. Write up your experiences along with your estimates and comment on one other student

Videos:

1. Water Waves 4
2. Water Waves 5
3. Young’s Double Slit Experiment
4. Double Slit
5. Arago Spot