丁香园AV

Concepts

Doppler effect

Overview

Swing around a battery-powered buzzer on a string to get a Doppler shift in the sound.

Details

Equipment

• [1] Buzzer on a string
• [1] Earmuffs

Important Notes

• Be careful not to lose grip on the buzzer and let it hit someone.
• The buzzer is a bit loud and annoying.

Script

1. [Optional] Put on the earmuffs.
   
2. Flick the switch soldered to the buzzer so that it emits sound.
   
3. Wrap a segment of the buzzer's string securely around your hand.
4. Swing the buzzer in horizontal circles over your head or in vertical circles to your side.
5. Flick the switch the other way to stop the sound.
6. [Optional] Take off the earmuffs.
   

Additional Resources