Homemade Telephone...!

Homemade Telephone

Materials Required;

Two Plastic cups or Coffee cups, long piece of string.

Now, What a great thing the telephone is! Talk to any one who is near and dear to you, whenever you want without caring about the distance at all! But, one minute! The telephone you'll make here will help you to talk just in and around your place, the farthest you can go is to the street corner and have a chat with a friend across.

To make this homemade telephone, take two small plastic cups and make a small hole in the base of each. Now pass your string through these holes and tie knots so that the string doesn't slip back through the holes. Yes, make sure to keep the cups opening in the opposite directions. That's all, your
telephone is ready.

Give one cup to some friend and ask him to put its open end on his ear.

Now stretch the string fully and, standing at a distance, speak into your cup keeping it close to mouth,
"Why man, what about having a dinner with me tonight?" Having asked the question, now change
the position of the cups i.e., put your 'mouth-piece on your ear and ask your friend to put his 'earphone' on the mouth. Now you'll be able to hear clearly how your pal reacts to your dinner invitation. But, how does it happen? Do you know the theory behind it? When

you speak into the box, your voice produces sound vibrations in it.

These vibrations travel through the string and produce the similar kind of sound waves in the other cup too. The air inside the 'earphone' is affected and the same so heard which you and your friend
produced alternately.