Make a string telephone
Making a string telephone is a fun way to talk with a friend or your sister or brother after the lights have gone out. It may be simple technology but before the days of mobile phones and computers, people had to be more inventive. Get calling your friends today!
What you need:
- 2 paper cups or tins
- sharpened pencil or skewer
Number of players:
Poke a small hole just big enough to fit the string through the centre of the base of each paper cup or tin with a sharp object, such as a pencil for cups or a metal skewer for tins.
Draw the end of the string through one of the cups/tin and tie a knot in it to anchor it in place.
The knot should sit inside the base of the cup/tin.
Repeat these steps with the second cup/tin, tying a knot in the string through the base of the second cup/tin too.
Your string telephone is now ready to test.
Hold one paper cup/tin up to your mouth and talk loudly into it. Your friend should walk away as far as the string will stretch and keep it tight.
Your friend should hold the other cup/tin up to their ear.
If the string is tight, your friend should be able to hear your message through the cup/tin!
- A string telephone works because of the vibrations your voice causes along the string. The vibrations travel like waves along the string and when they reach the other end of the string, they hit the second cup and turn back into sound.This is what your friend can hear. Amazing isn't it?