PROCEDURE 1: Build your own "string telephone."
(1) Fold a piece of tracing paper over one end of each of your cardboard tubes.
Hold it in place by putting a rubber band around it.
(2) Pull the paper tight and secure it with some tape.
(3) Using the lead end of a pencil, poke a small hole in the tracing paper that is
connected to your tubes. Do this for both tubes.
(4) Insert string into the holes in the tracing paper of each tube. Once each tube
is threaded, tie a paper clip to the end of each string so the string does not slip
through the tubes.
(5) Your "string telephone" is now complete!
PROCEDURE 2: Gently pulling the string tight, one person should place a tube to his
or her mouth and talk into is as the other person holds the other tube
up to his or her ear. Switch roles. Do you hear anything? Can you
tell what your partner is saying?
PROCEDURE 3: Join another group and make a four-way connection. Does the
"conference call" work?
PROCEDURE 4: Answer the following questions in complete sentences. Be as specific
as possible with your responses. You may use another sheet of loose-
leaf paper and staple it to the back of this lab sheet.
(a) Did your "string telephone" work? Why or why not?
(b) When you heard a sound in the tube, what acted as: (a) the source; (b) the medium;
and (c) the receptor?
(c) Using the terms discussed in class, explain precisely how your "string telephone"
worked.
(d) Was your four-way "conference call" successful? Why or why not?
(e) Does this experiment prove that sound is a mechanical wave that is longitudinal in
nature? Why or why not?
(f) Knowing what you do about sound, use the terms discussed in class to answer the
following question: If a tree falls in the forest and no one is there to witness it, does it
make a noise?
(g) What is one new concept or idea you learned from this lab? Why is this new
knowledge significant to you?
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