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seismic P-waves for all available earth- quake events occurring between 2005–2007. The average velocity of P- waves for each earthquake event was determined by dividing the surface dis- tance of the epicenter of the earthquake to the selected seismogram station by the time it took for the P-waves to arrive at that designated seismogram station. This process was then repeated for each earthquake event across three seismographic locations in California. A total of eight earthquakes in California were studied for this experi- ment. Each event was recorded from three different seismographic locations to make a total of 24 data points for this experiment. In this experiment, the formal hypothesis was that earthquakes with a larger magnitude would cause faster seismic P-waves. There was no pattern found in the magnitude com- pared to the velocity of P-waves for this data set, which shows that the velocity of a seismic P-wave can vary with the magnitude of an earthquake. An unex- pected finding was that there was a relationship between the distance trav- eled by the P-wave and the velocity of
the wave. In all eight of the earthquakes studied, it was shown that as epicental distance increased so did the velocity of P-waves. This increase in velocity could be due to a change in the medium the waves were traveling through.
Jennelle Allen
Santa Fe Christian Schools, Solana Beach, CA
7th Grade
My hyphosis was that I could determine which instrument produced a particular sound by analyzing the sound using electronic measurement instruments. My procedure was that first I played the C-scale (8 notes from C4 thought C5) on the violin and then on the harp. I recorded it and then used a spectrum analyzer and oscilloscope to look at the sound waves. The results were that they were significantly differ- ent. On the harp, the note is typically the fundamental while on the violin, there are usually many harmonics after the fundamental. Another thing I found is that the harp had a large attack and a slow decay, but the violin gradu- ally got bigger and stayed at that point.
Jennelle Allen
When playing the note stopped, the violin decayed much faster than the harp. The conclusion was that I was correct because there was a noticeable contrast between the harp and the vio- lin and these differences could be used to determine which instrument played the note.
—Robert J. Vent, ASA judge
USA Meetings Calendar
Listed below is a summary of meetings related to acoustics to be held in the U.S. in the near future. The month/year notation refers to the issue in which a complete meeting announcement appeared.
2009
18-22 May
26-30 October
157th Meeting of the Acoustical Society of America, Portland, OR [Acoustical Society of America, Suite 1NO1, 2 Huntington Quadrangle, Melville, NY 11747-4502; Tel.: 516-576-2360; Fax: 516-576-2377; Email: asa@aip.org; WWW: http://asa.aip.org]. 158th Meeting of the Acoustical Society of America, San Antonio, TX [Acoustical Society of America, Suite 1NO1, 2 Huntington Quadrangle, Melville, NY 11747-4502; Tel.: 516-576-2360; Fax: 516- 576-2377; Email: asa@aip.org; WWW: http://asa.aip.org].
2010
19-23 April
15-19 November
158th Meeting of the Acoustical Society of America, Baltimore, MD [Acoustical Society of America, Suite 1NO1, 2 Huntington Quadrangle, Melville, NY 11747-4502; Tel.: 516-576-2360; Fax: 516-576-2377; Email: asa@aip.org; WWW: http://asa.aip.org].
2nd Iberoamerican Conference on Acoustics (Joint Meeting of the Acoustical Society of America, Mexican Institute of Acoustics, and Iberoamerican Federation on Acoustics), Cancun, Mexico [Acoustical Society of America, Suite 1NO1, 2 Huntington Quadrangle, Melville, NY 11747-4502; Tel.: 516-576-2360; Fax: 516-576-2377; Email: asa@aip.org; WWW: http://asa.aip.org].
National News 37