Sound Explorations

My youngest had gotten this set of water flutes for Christmas. The boys had played with them in the bath, but I got them out today and we used the cards that came with it to play some songs such as Old MacDonald had a Farm. The flutes play different notes depending on how much water is put in them. We talked about how the highness or lowness of a sound is called Pitch. (They are so cool! I highly recommend them as a toy.)

Have you ever made sounds with a glass and some water? Moisten a finger with water and rub it evenly around the top of a glass to make a ringing sound.

Ben Franklin designed a version of this called the glass harmonica. This instrument had a row of glass bowls mounted on a long axle attached to a wheel. The lower half of the bowls rested in water. The player used the fingers of both hands to rub the wet glasses as they turned.

We also talked about how air is not the best conductor for sound. Sound actually travels much more quickly through solids. I rapped on the table and they listened and then I asked them to put their ear to the table and I rapped on the table with the same volume and they immediately could see that the sound waves traveled much more quickly and thoroughly through the table. Speaking of sound as vibrations, this is easily demonstrated by having your kids whisper and put their fingers on their throats and feel for the vibrations. Then have them shout and feel for the vibrations. Now have them sing with high notes and low notes. Low sounds are caused by slow vibrations, which can be easily felt, and high sounds are made by faster, smaller movements that are harder to feel.

All sound is created by vibrations. When a sound is made, the molecules vibrate. Those vibrating molecules make the other molecules around them vibrate, and so on and so on until the molecules in your ear vibrate. Once in your ear, those sound waves cause your ear drum to vibrate. This sends signals to your brain that a sound is heard. These traveling vibrations are called “sound waves.” If there are no molecules to vibrate, then no sound is created. That is why there is no sound in a vacuum such as in space.

Both sound and light move in wave patterns.  Have a student hold one end of the rope and you take the other end and raise your arm up and then bring it down, creating a wave.

Then have them lay out a rope, in a wave pattern they saw when they were moving the rope, on a table for students to sketch...

and you can teach them the vocabulary about sound and light waves to add to their sketches.

Resources:

• You can make your own set of flutes with jars and water. Plot 55 has a wonderful demonstration on how to make the notes by color... Students fill jars with water and arrange the sounds they make, from high to low, and then add color to the water. The students then wrote a bit of a tune and then recorded this tune on a piece of paper with circles by duplicating the colors of the waters onto the circles on the paper. The tune then could be duplicated by different people or at different times. This is a great introduction to music notation.