PURPOSE: To demonstrate the Doppler effect.

DESCRIPTION: A speaker with a string attached whirled about the instructor's head. The Doppler effect can easily be heard throughout even a large room. You can also play doppler football and get the same result.

SUGGESTIONS: Practice is required to play doppler football.

EQUIPMENT: Speaker on a string, or doppler football

SETUP TIME: 15 minutes

KEYWORDS: doppler effect