Talk Across a Distance

Design, test, and improve a cup-and-string phone or a sound code.

Warm-up, learn, try it together, practice, then a quick check. About 15 minutes.

What children learn in Level 48

Now you can be an engineer! Your job: send a voice across a room with no electricity, using two cups and a string.
Your voice shakes the bottom of the cup. The cup shakes the string, and the string shakes the other cup. Your friend hears you!
Keep the string tight. A loose string can't pass the vibrations along.
Pinch the string, and the sound stops. Your finger keeps it from vibrating.
Try it with a grown-up: build one, then test different strings and cups. Change one thing at a time, measure how far it works, and improve it.

Georgia Standards of Excellence in Science:

S4P2.b — Design and construct a device to communicate across a distance using light and/or sound.