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Clucking cup

By David, 16 September 2021 Activity

A person holding a paper cup with string attachment and a musical note in speach bubble above.

Noisy vibrations make a clucking sound

Want to surprise your friends and family? With a bit of practice, you can make this cup cluck like a chicken!

You will need

  • String
  • Scissors
  • Paper cups
  • Wooden skewer
  • Wooden toothpick
  • Thin sponge
  • Paper towel (optional)

What to do

  1. Cutting string with scissors.Cut a piece of string about 60 centimetres long.
  2. An upside down paper cup.Put a paper cup upside down on a table.
  3. Piercing a skewer through the bottom of a paper cup.Carefully poke a hole in the bottom of the cup with a skewer.
  4. Using the skewer to poke the string through the hole in the bottom of the paper cup.Use the flat end of the skewer to carefully poke the string through the hole.
  5. Three short broken pieces of toothpick.Break the toothpick so you have a piece about 2-3 centimetres long.
  6. Tie a piece of toothpick to the string coming out of the bottom of the paper cup.Tie the piece of toothpick to one end of the string – either end will work.
  7. Toothpick tied to the string coming out inside the cup.Pull the other end of the string until the toothpick is on the bottom of the cup.
  8. Wetting a blue sponge with water from the tap.Slightly wet your sponge.
  9. Holding the sponge in one hand and the cup in the other.Hold the cup with one hand, and the sponge with the other.
  10. Pulling the string through the cup with the damp sponge.Use the sponge to grip the string firmly, and then pull jerkily. If you do it right, you’ll make a loud, surprising, clucking noise!

 

Troubleshooting

If your cup doesn’t cluck, there are plenty of things you can try!

  • Try squeezing the sponge harder or softer, and pulling the string faster or slower.
  • Try using a damp paper towel instead of a sponge.
  • Try wetting the string, and then pull on the string without a sponge.
  • Try a different type of string. We found cotton string works well, and so did curling ribbon.

What’s happening?

As you start to pull, pressure on the string and sponge causes them to stick together. But as you pull harder and harder, the string stretches, the sponge bends and even the bottom of the cup starts to flex.

Eventually though, the force is too much and the string starts to slide through the sponge. The string relaxes, the sponge unbends, and the cup returns to normal while the sliding continues.

If everything is just right, the string and sponge will stick again just as everything unbends. Then it slips and sticks over and over, many times every second.

The slipping and sticking vibrates the string. But most of the noise comes from the bottom of the cup. It gets pulled every time the string sticks, and released every time it slips. The bottom of the cup vibrates back and forth like a speaker cone! The rest of the cup also works as a horn to direct and amplify the sound even further.

Did you know?

Have you ever pushed a chair across the floor, making a loud noise the whole time? Believe it or not, it’s making noise in a similar way to your clucking cup. Both are a matter of sticking and releasing, causing noisy vibrations.

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1 comments

  1. Add an orange paper comb and some google eyes for lots more fun – I used to make these with my class every Easter. You can even get a chook choir going with some appropriate chicken dance music.

      Reply

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