I remember trying this hanger and string sound lesson when I was younger. I came across it again while searching the internet one day and knew that my girls would love it!
To try this sound wave experiment yourself, you’ll need a wire coat hanger, yarn, and objects to hit the coat hanger against (a wall, a table, something else metal…). That’s it!
1) Tie the yard onto the hook of the hanger leaving (about) equal amounts on both ends of the yarn.
2) Start by hitting the hanger against an object and listen to the sound.
3) Next, wrap the ends of the yarn a few times around your pointer finger.
4) Lightly put your fingers in your ears (do not plug your ears completely)
5) Hit the hanger in the same spot again, this time with your fingers in your ears.
How is the sound different?
My girls spent quite a while hitting the hanger against different objects to see how the sound varied. It sounded different against metal than it did against wood and even tile.
Why does it sound different when the string is in your ear vs not?
Sound is made of vibrations. When you hit the hanger against something, it vibrates (moves back and forth). This makes the air around it vibrate. You hear sound when the vibrations travel to your ear. When you listen to the hanger with your fingers in your ears, the vibrations travel through the string and into your ears vs traveling through the air to your ears. It sounds different because sound travels differently through string (a solid) than through air (a gas).
Even I had to have a little fun with this experiment again!
To add some variety, try different types of string such as fishing line or thread. You can also hang objects from the hanger to see how that changes the sound.