# Why Sound Doesnt Travel Through A Vacuum

• Keeling16
In summary, sound waves cannot travel through a vacuum because they require matter to propagate. This can be demonstrated by using an alarm clock, a bell jar, and a vacuum pump to show how sound diminishes in a vacuum. It is important to perform experiments in physics classes to better understand concepts.
Keeling16
Hey guys!
I am just wondering if any of ya'll can help give me a good in depth understanding of "why sound waves can not travel through a vacuum".

Also if any of ya'll know how to show a class presentation of how to demonstrate this and good instructions on how to make this object please let me know a.s.a.p.

I would deeply appreciate it!

Thanks...

"Sound" refers to waves of compression which travel through matter. When there is no matter, there can be no such waves, and therefore no sound.

- Warren

The animation of the longitudinal wave on http://www.kettering.edu/~drussell/Demos/waves/wavemotion.html is a good example of sound waves. If those were molecules of air they would continute bouncing like that until they hit your ear drum and then you would hear sound. Without those molecules or any others there could be no compression waves and no sound.

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You can demonstrate this of front of class by taking an alarm clock, a bell jar and a vacuum pump.
Let the alarm clock ring and put the jar on top of it. As you pump away the air from the jar the sound will diminish until it is gone completely. When you let the air back in, you'll hear the sound again.

Hopefully (probably) they'll have the necessary equipment at your school. Physics at school should always be accompanied by experiments.

## 1. Why doesn't sound travel through a vacuum?

Sound is a type of mechanical wave that requires a medium, such as air or water, to travel through. In a vacuum, there is no medium for the sound waves to vibrate and propagate, therefore sound cannot travel through it.

## 2. Can sound travel through outer space?

No, outer space is mostly a vacuum with very low concentrations of particles. This means that sound cannot travel through it as there is no medium for the sound waves to travel through.

## 3. How does sound travel through air?

When an object vibrates, it creates sound waves that travel through the air molecules, causing them to vibrate and pass the sound along. The closer the air molecules are together, the faster the sound waves can travel.

## 4. Can sound travel through liquids or solids?

Yes, sound can travel through liquids and solids because they have a higher density of particles compared to gases. This allows sound waves to propagate more efficiently, resulting in a faster speed of sound.

## 5. Why is sound unable to travel through a vacuum but light can?

Sound is a mechanical wave that requires a medium to travel through, while light is an electromagnetic wave that can travel through a vacuum. This is because light does not need a medium to propagate, as it can travel as both a wave and a particle.

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