Speed of Sound
The speed of sound laboratory was done using a GPS and a ten second count as I have done for a few terms now. The lab led off with the determination of the relative humidity. I displayed the projected speed of sound from WolframAlpha using a Nokia Asha 311 I acquired in early October. During the lab I then ran checks of our data against the expected value. This was used to inform the clapping process. Above Dwayne is working on synchronizing to the echo, Allston is working the stop watch. Marvin, Merany, and Brian Tonga are looking on.
The use of the expected value in the field was new, effectively an inversion of the previous terms where the speed of sound was kept under wraps until the end of the laboratory. Berry used the GPS to gather distance data on the longer walks. In the afternoon one student went into the cafeteria to get a drink during the measurement run. The data was off significantly as a result.
In addition, as I have done the past few terms, the data was plotted in the field. The morning class used the front porch of the gym complex. The afternoon class ended at the cafeteria.
The white board notes a morning dry bulb temperature of 25 °C, wet bulb of 23.5 °C for a relative humidity of 88%. By 11:00 the dry bulb had climbed to 26 °C, the wet bulb to 25.5 °C, for a relative humidity estimate of 96%. The morning sound speed was about 348 m/s, about the same in the afternoon.
Marcyliza was detailed to gather distance data from the LRC based on the necessity of passing through the hand railing at the end of the sidewalk. She was an excellent sport and went out and back through the railing.