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Science Rocks!

Stereo Hanger


your results

Sent in by:
Stephen of Germantown, TN

Sound wave science, in stereo!

Materials Needed

  • metal coat hanger
  • string
  • bowl of water
  • metal spoon
  • table



  1. Tie the ends of a piece of string to each corner of a metal coat hanger.
  2. Then loop one end of the string around one index finger and the other end around the other index finger.
  3. Put your fingers in your ears and bang the hanger against a table.
  4. The sound waves from the vibrating hanger travel through the string and into your ear.
  5. Do the same thing with a metal spoon.

Now try experimenting. Different materials vibrate differently. See if you can hear a difference in the way a muffin tin sounds. What do you think will happen? Make a prediction. Then change one thing-that's the variable-and test it out. Be sure to tell us what you thought was going to happen and what actually did happen. When you're done, send your reports to our special feedback area. Every week we'll post new results from ZOOMers' Stereo Hanger experiments.

Some of your Results

Year 5 Class, age 10 of Swadlincote wrote:
We tried this experiment with a fork, a spoon and a plastic ruler. We were looking at the different sounds that different objects made. We found that by putting our fingers in our ears, the pitch got lower. We think this is because the sound that travelled through the air (gas) before, now travels through the string (solid) making the sound lower in pitch. We also found that the vibrations were stronger in the fork, because the metal conducted the vibrations better. There was no change in the spoon because they have a similar structure. In general, we all enjoyed this experiment, it was wicked!

Quincey, age 12 of Fresno, CA wrote:
I tried doing something like this before. I would put my ear on my desk and tap it its very loud and when you close your ears and whisper it sounds way louder.

Jessica, age 10 of Pittston Twp., PA wrote:
I heard the difrence. I think it was really cool to try it!

Jessica, age 8 of E. Strousburg wrote:
When I banged the hanger on the table it made a lower sound then the spoon.

Rachel, age 11 of Daytona Beach, FL wrote:
The hanger worked, but... the spoon was too short!

Zachary, age 5 of Palmyra, PA wrote:
I tried different sized spoons to see if the different sizes made different sounds. The biggest spoon made the lowest sound. It was awesome!

Meagan, age 12 of Little Falls, MN wrote:
I thought it was really cool. It's kind of like when you try to talk to some one else through two cans and a long string!

Mary, age 12 of Oaklawn, IL wrote:
It was hard to do with one person. But I did it. It was fun!!!

Haylee, age 10 of Beaverton, OR wrote:
I used a medal spoon and a coat hanger And some Red string, And when I did it sounded great to me, And you guys did great.

Olivia, age 7 of Hillsborough, NJ wrote:
I used a plastic and a metal hanger. They both sounded alike.

not yet implemented