The sound makes each can to vibrate and this vibration is transmitted along the string connecting the two cans.
What we need :
- 2 clean and empty cans,
- +-20 m (+-21yd) of string.
- Clean the cans;
- Make sure the can has no sharp ends;
- Place the cans, upside down, on a hard surface;
- Punch the center of the cans with the nail;
- Pass the string through the hole of the first can;
- On the end of the string attach a paper clip;
- The other string end goes on the second can, using same method, when you finish you will have 20m of string attached to 2 cans, one on each end;
- Give your restless one of the cans;
- Walk away until the string is fully stretched;
- Ask your child to place his/her can on the ear;
- Talk to the can;
- Now it's your turn to listen.
When we talk the air vibrates, thats how the sound travel, the can also vibrate, those vibrations travel along the string to the second can, this causes the air in the second can to vibrate, producing sound.
Fun fun fun!