Introduction to Sound

For this experiment we observed the wave patterns created by sound. Using Logger Pro, we were able to view the patterns created.

First, a student from our group said "AAAAA" smoothly into the microphone and collected data. The wave patter created is shown below.

Here we see that this wave is periodic, the same pattern is created from the highest point to the next.

In the .03 seconds of data collected 3.5 waves were created.

The period of the wave was approximately .0085 seconds, which was determined by reading the time of one wavelength on LoggerPro.

The frequency was approximately 117.6 Hz, which is the reciprocal of the period.

f=1/T

The wavelength was 2.89m, which was calculated using a relationship between the speed of sound and frequency

wavelength (lambda) = speed of sound/frequency = v/f

The amplitude was determined by reading the length from the middle of the wave to its highest point, the aplitude for this wave was 1.8 (arbitrary).

If the duration of the sample was changed 10 times longer the wave properties will not change. The same pattern will appear but the only difference is that there will be 10 times more waves on the screen as shown below.

The experiment was done once more with a different student and the wave created is shown below.

Now, the same experiment was done using a tuning fork instead of a human voice.

Using the same tuning fork, we collected data for a sound that was not as loud.