3D22.25 - Cup Telephone

Make sure the string is taut between the two cups and then speak into one while someone is listening at the other cup.  The words spoken can be clearly heard by the listener.
Code Number:
3D22.25
Demo Title:
Cup Telephone
Condition:
Excellent
Principle:
Sound Transmission
Area of Study:
Acoustics
Equipment:
Cup Telephone system
Procedure:

Make sure the string is taut between the two cups and then speak into one while someone is listening at the other cup.  The words spoken can be clearly heard by the listener.  

References:
  • W- 020:  "Tin Can Phone - Coat Hanger Amp.", DICK and RAE Physics Demo Notebook.
  • George M. Hopkins, "Conduction of Sound", Experimental Science, p. 125.
  • Carson I. A. Ritchie, "Cardboard Telephone", Making Scientific Toys, p. 52.
  • "Let's Play Telephone!", Exploratopia, p. 347.
  • Christopher P. Jargodzki, Franklin Potter, "Simple String Telephone Line", Mad About Physics, p. 59.
  • Neil A. Downie, "String Radio", Vacuum Bazookas, Electric Rainbow Jelly, and 27 other Saturday Science Projects, p. 83.
  • Charles Vivian, "A  L O N G E R  Path", Science Experiments & Amusements For Children, p. 40.
  • Martin Gardner, "Paper Cup Telephone", Smart Science Tricks", p, 116.
  • Herb Strongin, “Making a String Phone“, Science on a Shoestring, p. 145. 
  • Prof. Robert Griffith, "A Telephone For Short Lines", Boys' Useful Pastimes, p. 83.

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