- Drinking straw
What to do:
- Flatten one end of the straw by sticking it in your mouth and biting down with your teeth, and pulling it out. Do this a several time to make a flexible flat-ended straw.
- Cut equal pieces of the straw from each side of the flat region so that the straw has two lips at the end.
- Put the straw in your mouth and bite down gently with your front teeth just beyond the lips of the straw.
- Experiment with blowing hard and softly while biting down with different amounts of pressure until you make the straw sing.
When you blow, a pulse of compressed air flows down the straw. The pulse travels down the straw at Mach 1, the speed of sound, and bounces off the distant open end.
When the sound bounces off the open end, the compressed air changes into a low-pressure expansion. When the expanded air reaches the lips of the straw, they are forced closed – then bounce open to admit more air. The sound bounces back and forth inside the straw and the lips of the straw open and close to create a sound.
And for some new sounds:
Try making the straw shorter Make holes in your straw like a flute
Find another straw that can fit inside of your oboe. Pull it in and out like a trombone. Roll a piece of paper into a cone and tape the cone onto the end of the straw to make a straw oboe with a bell. The bell makes less sound bounce off the end of the straw so that more sound goes out into the air. This makes the sound much louder.
Adapted from: www.exploratorium.edu