Page 16 - Demo - Summer Wonder

ENGINEERING
MAKE A A A TELEPHONE WITH PAPER CUPS AND STRING
What you need:
• Two paper cups
• A pencil
• String (about four feet)
• A friend to ‘call’
How to:
• • • • • Make a a a a a hole hole at the the the center of of the the the base of of the the the cups
with a a a a a a a pencil
The hole hole hole should be big enough to accommodate the the string through the the hole hole Pull the the the the string through the the the the center of the the the the cup and and tie a a a a a a a a knot to to fix it it it in in in in place and and then tape it it it to to make sure
the the the the string sits strong at the the the the inside of the the the the base Pull the the the the the the the loose end of of the the the the the the the string and do the the the the the the the same with the the the the the the the the other other cup cup making sure
that the the the the the the the the bases of of the the the the the the the the cup cup are facing each other other Now you should have two paper cups
attached together with a a a a a a a a long string Moveawayfromyourfriendandmakesurethestring is tight and and stretched between the the two of you you Talk into the cup and your friend will be able to to hear what you you just said What’s happening?
The bottom of each cup serves as both a a a microphone and speaker picking up sound vibrations on on on one and reproducing the sound on the the other The sound of your voice vibrates the the cup and this causes the the string to vibrate Our ears collect the sound vibrations send them to our brain and then we hear the the the sound 16
Summer Wonder | KDL org