Waves, Oscillations, & Acoustics: Bell in a Vacuum

PIRA Class: 3B30.30

Purpose

To demonstrate that sound waves require a medium for propagation.

Description

Start the bell for students to note the sound of the bell under the bell jar.

- Turn pump on, wait ~ 2 minutes to produce a good vacuum, during which the sound intensity will decrease

- Turn off vacuum pump and slowly let air back into bell jar, during which the sound intensity will increase

Equipment

Bell jar & doorbell

Support Equipment

Vacuum pump

Location:

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