Let us do a classic Physics experiment called the “Rubin’s Tube”.
Now, I really want to bring it down that it involves open flames, and some people have issues with open flames. So, what we have here is a length of PVC pipe, it has about 100 or so holes drilled at half inch increments. We have some foil tape keep it from melting. On this side, we have a two-inch speaker matching the diameter of this two-inch tube, and on that side we have some lab tube leading to some propane. So, let us fire it up and see what it does. (Demonstration)
As you can see, we have some nice standing planes, a little bit of oscillation from the vibrations in the hole. Let us throw some sound in there and see what happens. Let us start with a 449 hertz frequency. (High-pitch sound)
As you can see, this acts as an outstanding wave and we can see well the emerging sign curve that represents sound. What happens here is having the sound compressing here, and not compressing here. The lower pressure here allows more gas escaping the atmosphere, shaping the sound curve.
Now, we change the frequency. (High-pitch sound) We can see that each time we set up a standing wave, we get that sound curve. The higher the frequency, the more waves. Now, let us throw some music at this. How about some Dave Rivet? (Music playing) Now, we have real-life sound visualization. It is fun.
I cannot be reckless and terribly energetic, so let us try something a little more energetic. (Music playing) Alright, now that is a good music. Now, let us turn off the gas and have some fun. (Music playing) That is the Rubin’s Tube.
Transcription by:
Scribe4you Transcription Services