Sunday, July 11, 2010

Science Sunday - Seeing Sound

My seven year old commented at breakfast, that he thought he would be be able to hear his brother chewing, clear from the moon.

My answer, of course, was, "No dear, there's no atmosphere on the moon for sound waves to travel through, so you wouldn't be able to hear anything at all there."

When he gave me a blank stare in return, I knew we were in need of an experiment. This is another one (slightly modified) from Robert W. Wood's what? experiments for the young scientist, which has definitely moved to the top ten of my favorite science books list.

First, I showed him how a drop of water causes waves to move through a bowl of water.

Then, I cut a dime size hole in the lid of an empty coffee can (Woods suggest using an empty salt container, or oatmeal box).

I lit a candle in the middle of the table. After, the children had observed the candle flame for a while, so they could see it was still, and not being moved by any breezes, I had them point the hole in the coffee can at the flame, and tap the bottom of the can.

Each tap, caused the flame to move and dance, in time with the noise.

We tried tapping the can farther away from the flame, and closer to it, to get an idea of the range of the sound waves.

Finally, we watched The Magic School Bus In The Haunted House (you can watch it for free, here, on for a child friendly explanation of sound waves, and how they work.

For more fun with science, check out the Science Sunday blog hop, hosted by Adventures in Mommydom.

It's great to be a homeschooler.


Debbie said...

A very interesting experiment. I was trying to remember how we studied sound waves, but I believe it was just with the water. I like this one, as it explains more clearly sound waves traveling through air.

Cindy said...

Great experiment! I'm going to bookmark this for when we talk about the five senses!

Unknown said...

Very clever experiment. I can just imagine the look on his face when you told him " you can't hear him chewing". Thanks again for another wonderful experiment.

Christy Killoran said...

Very cool!

Joyful Learner said...

So clever! I've bookmarked this!

Natalie PlanetSmarty said...

I like this experiment. Just yesterday when we went sailing Anna commented how the sail "catches the wind". It would be neat to show her that it's possible to "catch the sound" too.

Phyllis said...

This is unschooling at its as it fits with the day and conversation.

Ticia said...

We did this on a much larger scale at the children's museum recently.