Having Fun with String Telephones : A Science Activity

Not a Smartphone.

No, not a smartphone but this one is definitely cool!

Kids are having fun with a new toy we made recently. It is amusing how in the middle of technological advances and high-tech toys, kids still find joy in the most basic instruments.

Coincidentally, our current homeschool topic in Science is all about SOUNDS so I thought why not make this simple experiment.

The Tin Can Telephone

The idea is to make a device which will let you communicate with someone using 2 tin cans and string.

Sound travels through mechanical waves or vibrations, from one place to another medium. The medium can be solid, liquid or gas. In this exercise, the vibrations will come from the voice which will travel through the cotton string.

Materials Needed:

• 2 empty tin cans
• yarn
• hammer and nail

Procedure:

• Simply put a hole at the center of each tin can and insert the ends of the yarn on each hole. Secure the yarn by making a knot. So that the yarn will not be pulled out, you can also lock it by tying a short piece of toothpick at the end of the yarn.

• Once done, give one can to your partner and get as far away from each other as the string can allow. The speaker should speak through the can in a manner loud enough, not a whisper and also not too loud. On the other end, the receiver shall put the can over his/her ear and cover the other ear with his/her hand.

"What did you just say?!"

We did this exercise before, but for some reason it was not successful. I concluded it was because of the string we used. We used a nylon fishing line on our first experiment. I could not find my yarn in my stash that time. lol

This time around, the kids have fun "sending messages" to each other. I also join the fun just to make sure that they really hear from inside the can and yup! It really works!

Observations

The sounds made were clearer when the string was held straight and tight. This was because sounds the vibrations are travelling though a solid material. If the string is not straight, the vibrations dissepate and do not reach the other end.

---

_{All images are by the Author taken via Samsung Galaxy Note 3 .}

---

_{banner by @enginewitty}