Cup Telephone Distance Test

Sound is much clearer with taut string. Ask students to predict what will happen. Speak through the cup with string taut, then loose. Key idea: Vibrations travel through the tight string between cups. Ask: Why does a loose string work poorly? Safety and cleanup: Use clean cups; no neck wrapping. https://www.google.com/search?q=%22Cup%20Telephone%20Distance%20Test%22%20science%20demonstration%20experiment