A Musical Day

Well, sort of... dog clickers and virtual keyboards made for a noisy day, at least...

B Block worked on an investigation that had them experimentally determine the speed of sound and compare it to the ballpark values we've used in class and to a calculated value based on the temperature of the room. Students then used hair dryers to heat up the air in their PVC tubes and saw that, as predicted, the speed of sound increased. Tomorrow is a combo period. We'll spend the first part reviewing the items for the test and then working on a lab that focuses on the mathematics of music.

C Block conducted both their Speed of Sound and Mathematics of Music labs. The speed of sound was determined using the distance/time relationship and the effect of temperature was tested using a hair dryer to warm the air in the PVC tube. Unsurprisingly, in a warmer environment, the wave moved more quickly due to the increased kinetic energy and velocities of the air particles. For the music portion, students used a Java applet called TuningFork, which provided them with a virtual piano on the laptops. When a key was depressed, not only was the sound audible, but the frequency of the note was displaced. Students looked at the frequency ratios between adjacent notes also between notes and the standard middle C. Tomorrow, we'll go over these labs and review for Friday's test.

E Block started their review for Friday's exam, then took time to work on some of the more troublesome mathematical concepts in the chapter. We'll go over these problems tomorrow and address any last minute concerns on the material.

F Block discussed the idea of beats and beat frequency in class. Beats are an interference phenomenon that produce alternating constructive and destructive interference. The number of audible beats per second (beat frequency) matches the frequency difference between the two source tones. Tomorrow is set aside for review, so come with questions about the material in this chapter.