The Science of Soundwaves

4 foot length of string or yarn

small spoon

large spoon

experiment with other utensils and observe the results

ruler (a wooden or heavy plastic ruler work best - if you don't have one, try a wooden spoon?)

First, create a loop in the middle of the yarn/string and insert the handle of the spoon.

Pull tightly so that the spoon hangs in the center of the yarn/string and you have two long pieces of approximately equal length.

Take each string and wrap them around your pointer finger on each hand.

Then push the string against each ear (not into the ear but just outside like you are going to plug your ears because you don't want to hear your Mom ask you to do your chores :)

You'll want the spoon to hang just below the waist once both ends of the yarn are placed near the ears.

You can see in this photo that you don't have to use the end of each piece of yarn/string -- in fact, as you do the experiment, change how high or low the spoon hangs to see if it changes the sound.

Once the string in pushed against the ears, have someone GENTLY hit the ruler against the round part of the spoon -- and watch the look on your child's face (priceless!)

Warning: Kids often think that the HARDER they hit the spoon, the louder the sound -- be sure to test out this theory too!

If you are using a small spoon, you should hear a distinct bell sound -- with a larger spoon, it will sound more like a gong.

When the ruler hits the spoon, it creates vibrations which make sound waves. These sound waves travel up the yarn/string and to the ear instead of just spreading out into the air around you.

The yarn acts as a conductor -- an object that allows sound waves to travel.

Depending on the size of the spoon and the length of yarn, the sound will appear higher (like a church bell) or deeper (like a gong).

And because the yarn allows the sound waves to continue to travel, the sound of the spoon will resonate or reverberate -- meaning they will continue for a while after you have hit the spoon.

Another thing we found was that the only one who can hear the bell or gong sound will be the person with the string near their ears -- which we thought was also pretty cool.

Everyone else in the room will just hear a faint 'tink' when the ruler hits the spoon.

You can try other utensils around the house and compare the results.

Try different lengths or types of string - how does it affect the sound?