This is my brother with his violin because he had his orchestra concert this afternoon. While I was watching and listening to his orchestra concert, I thought again of physics, mainly the current concept of sound. My brother often rubs his bow with a block of rosin. I realized that this actually has a purpose! (No, I do not play the violin or any musical instrument for that matter...) The rosin creates friction between the bow and the strings on the violin so that the strings vibrate when the bow is pushed/ pulled over the strings. This vibration creates sound waves, oscillations in the air resulting from differences in pressure.
Before the concert actually started, the students had to tune their instruments. The teacher had to make sure that everyone's instruments were playing the same notes at the same frequencies, otherwise the audience would hear random weird noises throughout the concert...Each note has a specific frequency for a certain instrument, as we found in the lab with the super cool Casio keyboard (and our class totally did NOT press the demo button when doc left the room...right? :P). Also, the frequency of note doubles when it is played 1 octave higher, as higher notes have higher frequencies (1/T, cycles/s).
