Cup Phones

May 20, 2020  |   Sound, Technology, Making

Before cellular service, telephones were connected by wires. How'd that work? 

Jacob Copps rings up a simple experiment that sounds too easy to be cool. But generations of kids have wondered at the incredible ability of sound to travel through cups, cans, and a string. 

Materials | Supplies

  • paper, plastic, or yogurt cups
  • metal soup cans
  • nail, ice pick, awl, sharp pencil, scissors
  • string, yarn, fishing line, kite string
  • paper clips, toothpicks, tape, bobby pins

Concepts Explored

  • sound
  • vibration
  • making
  • tinkering

Discovery Starters

If the string is not tight, do you hear a sound?

What happens when you tough the tight string? Why?

How do different combinations of cups and string change the sound quality? 

Explore Further

Could you create more cup phone lines so more people could talk together? How? 

Why does a cup phone work? Could you amplify the sound? 

Additional Resources

Hip Hop Dog by Chris Raschka

Pokko and the Drum by Matthew Forsyth

Instructables website Simple Sound Experiments

Amazeum YOU Activity Guide Cup Phones

Amazeum YOU activities Metal Noise Makers | Funnel Horn | Balloon Saxophone