Whirly Tubes
MAKE SOME NOISE WITH WHIRLY TUBES! WHAT IS THE SCIENCE BEHIND IT?
EQUIPMENT
- Whirly Tubes
METHOD
- Hold one end of the tube and twirl the other end in a circle above your head
- Listen for the noise it makes
- See if you can do it a little bit faster and listen for the noise again
- Is it a different noise? What is the difference?
THE SCIENCE
Imagine that the tube is filled with tiny pebbles. Twirling the tube overhead would shoot the rocks out of the tube. The same thing happens with the molecules of air. As you twirl the tube, air molecules are launched out of the other end. The faster the twirl, the faster the molecules come flying out.
The faster the air flows through the tube, the higher the frequency of the sound produced which is then amplified by the tube.