One of the most well known of these experiments involved placing a ringing bell inside the jar, and observing that upon pumping out the air, the ringing disappeared.
This experiment demonstrated that the propagation of sound is mediated by the air, and that in the absence of the air medium, the sound waves cannot travel.
This experiment is often used as a classroom science experiment, where the experiment is repeated with an item such as an alarm clock placed under a bell jar, and the noise of the alarm clock fading as the air is pumped out being used to demonstrate the effect.
By additionally placing a microphone inside the bell jar and observing that the sound detected by the microphone reduces as the air is pumped out, the effect of absorbance of the sound by the glass of the jar itself can be excluded.
One of the most well known of these experiments involved placing a ringing bell inside the jar, and observing that upon pumping out the air, the ringing disappeared. This experiment demonstrated that the propagation of sound is mediated by the air, and that in the absence of the air medium, the sound waves cannot travel. This experiment is often used as a classroom science experiment, where the experiment is repeated with an item such as an alarm clock placed under a bell jar, and the noise of the alarm clock fading as the air is pumped out being used to demonstrate the effect. By additionally placing a microphone inside the bell jar and observing that the sound detected by the microphone reduces as the air is pumped out, the effect of absorbance of the sound by the glass of the jar itself can be excluded.
Bell jar