HOMEMADE TELEPHONE

In this experiment you will make a string telephone !

Materials:
2 paper cups
A long elastic string (the longer the better)
2 pins

Instructions

Make a hole at the bottom of the cup.

Now tie one end of the elastic thread to one glass and the other end to another glass.

And here your telephone is ready!

Now ask your friend to put the opening of the cup into his ear and you hold the other cup to your mouth and say a sentence, ask your friend whether he heard the sentence or not?

What happens?

When you speak from one glass sound vibrations are made. The sound vibrations travel through the string and the same sound vibrations are produced in the other cup! This is how your friend hears the sentence!!