1. The problem statement, all variables and given/known data A wooden stick, part of a musical instrument, which produces a musical sound when hit, oscillates by creating a transverse standing wave, with three antinodes and two nodes (3 "valleys", 2 "ground levels"). The lowest note has a frequency of f = 87.0 Hz, and is produced by a stick of L = 0.4 m a) Find the speed of the transverse waves in that stick. b) A vertical tube is hanging bellow the centre of the stick and boosts the intensity of the sound. If only the top part is open, how much of the tube's length must synchronize with the stick from (a) ? 2. Relevant equations f = n*λ/4L, n =1,3,5,7,9... 3. The attempt at a solution a) Okay, so the Standing Wave has the form of the Picture bellow: So, 4*(λ/4) = L <=> λ = 0.4 m v = λ*f f = 87.0 Hz ___________________________ v = 34.8 m/s b) Alright, I'm completely lost here. From what I'm getting, the tube follows the one end open/one end closed model. But doesn't the stick, that is inserted into the tube essentially "close" the open part as well? Even if that wasn't the case, all the formulas I know have to do with just a tube/stick/string, meaning that in this case where I have two kinds of material, I don't really know what to do. Furthermore, I don't really get how I'm supposed to approach this. It's not like I can put in the frequency and the speed to find the length or anything. Also, as far as "synchonization" goes, my book has no exercises on the subject, and just a small paragraph that explains the phenomenon, no formulas or anything. What I know about synchronization comes from the osciallation part, which is widly different from the waves, and has no bearing at this exercise. I'm really at a loss here. Any help is appreciated!